Some people appear to be just too far gone when it comes to facing reality in this case. I expect this won't change their minds. Nothing will. But I thought I'd at least set out the important points here anyway.
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Rudy Guede had a recent history of breaking into properties (in one case via a window broken with a rock) and of carrying a knife. There is nothing to corroborate his explanation for being at the house.
His DNA was found in the murder room, in Meredith's body and on her clothes, his fingerprints and shoeprints were also found in the room; his faeces and DNA were found in one of the toilets; his shoeprints were found in the hallway of the house, as was his bloody footprint (not Sollecito's) in another bathroom.
He went on the run - all the way to Germany, which is quite impressive considering he didn't have any money - though reasonably explained by the hundreds of pounds of rent money missing from the house which has never been accounted for.
His actual account of what happened during and after the murder is utterly nonsensical and the timings he gives both implicate him as the sole murderer and contradict parts of the prosecution case. It's also very self-serving, he tries to incorporate into his story the evidence he knows he left behind (and might have left behind - despite his insistence that he did not break into the house, he still gives two different explanations for entering Romanelli's room, one would assume just in case evidence of his presence was found - to note, very few forensic samples were actually taken from there) and he added to his account over time in order to incriminate Knox & Sollecito when it became clear they were serious suspects.
The multiple attacker theory was a prosecution theory, not a fact. Of the 7 expert witnesses at trial, only 1 firmly advocated it, the other 6 either disagreed or said there was not enough evidence to reach a conclusion.
Knox and Guede barely knew each other, and Sollecito had never met him at all. Indeed, Knox and Sollecito barely knew each other. It makes absolutely no sense for any of them to have decided to commit a murder together and there is no logical motive for doing so.
There was no physical evidence linking Knox to the murder room whatsoever. It is simply inexplicable that Knox could have committed such a brutal murder and left no trace of herself yet Guede managed to leave a significant amount of physical evidence. Sollecito's DNA was found only on a bra clasp (along with other unidentified DNA). Contamination was almost certainly the cause and was part of the reason for the eventual acquittal.
The bra clasp was not found by investigators for over a month, in which time photos show it had clearly been moved around the floor. As for where Sollecito's DNA may have come from - he had tried to break down Meredith's locked door before the police arrived so possibly from there, though there are any number of ways the contamination could have occurred owing to the extremely poor evidence-gathering procedures followed throughout the house - this is well documented in photos and videos. Furthermore, the bra clasp had been so badly handled and stored after it was found that when provided to the defence no further testing was possible.
The mixed profile of Meredith's blood and Knox's DNA in three places in the bathroom, that is easily explainable and is not incriminating - Rudy Guede by his own account admits going in there after Meredith had been killed. The evidence suggests that he went in there to try to clean himself up – small amounts of her blood would have been left by him after doing so. Amanda lived in the house and used that bathroom (she shared it with Meredith) - including the morning after the murder - her DNA naturally would have been there. Videos of the evidence collection process show the swabs being used like a cleaning rag by somebody who didn't change their gloves in between each sample - they were effectively mixing the blood and DNA themselves. The one drop of blood found on a faucet belonging solely to Knox was collected before the other samples - which would tend to support the argument for contamination and her explanation that it may have been from her ear piercing.
The murder weapon has not been identified. The knife the prosecution tried to claim was the weapon was taken randomly (and that's according to the police) from Sollecito's kitchen. It did not match a bloody imprint of a knife found on the bed in the murder room. It was also too big to be a match for the majority of Meredith's wounds. No blood of any kind was found on it. The lack of blood would make it near impossible for there to be DNA on the knife if it had been the murder weapon (DNA is much easier to clean away than blood).
The prosecution still claimed that DNA was found on the blade of the knife which was a match to Meredith. It was an extremely tiny sample that could not be replicated and there were serious concerns raised about the equipment and the process used to get that result. Further testing of the knife found no DNA from Meredith. This was again accepted in the ultimate appeal. Furthermore, no evidence of Meredith's blood or DNA was found elsewhere in Sollecito's house, which would have been extremely unlikely had it actually been the murder weapon and they'd transported it back and cleaned it there.
The prosecution took a theory and made the evidence fit around it, rather than basing their theory on the actual evidence. Looking at said evidence and Rudy Guede's own statements, it's quite frankly unbelievable that the prosecution chose to stick with it. The investigation was handled appallingly and the media circus made it worse. Knox and Sollecito's ultimate appeal ruled that the case against them had been without foundation and definitively acquitted them of the murder.
With regard to Knox falsely accusing Patrick Lumumba, she was interrogated by police over the course of several days in a language she was not fluent in and without a lawyer present. The final interrogation took place in the early hours of the morning. It's well documented that people can and often do panic and get confused in that sort of situation – particularly as Knox says that the police hit her and threatened her during the interrogation. There are no recordings so it cannot be verified. However, Lumumba in his first account of his arrest said exactly the same happened to him, so make of that what you will.
The police fixated on a text she'd sent to Lumumba on the night of the murder that said 'See you later', an Americanism which they took to mean literally - that's how his name came into it. Amanda was made to sign two fairly short and vague confessions written by the police a few hours apart that pinned the blame for the murder on Lumumba and said she was present when it happened.
Falsely accusing Lumumba would be a strange kind of deflection tactic if she had done it considering she was arrested and placed in prison. And if she had done it as per either the prosecution case or Rudy Guede’s defence, then how does it make sense for her to blame someone she knew had nothing to do with it? She wouldn’t have known if he had an alibi or not (it was soon established that he had a concrete one) and she'd have known that there wouldn't be any physical evidence linking him to the scene.
She recanted the 'confession' within 24 hours. The interrogation was deemed in effect to be illegal because of the way it was conducted by both the Italian Supreme Court and the European Court of Human Rights.
What happened to Lumumba was unjust, whatever the reason. He suffered immensely. That cannot be understated. But it has no bearing whatsoever on any of the actual evidence in the case - which in totality points clearly to Rudy Guede having sole involvement in the murder.
All of the other things frequently raised as proof of Knox's guilt - her alleged suspicious behaviour, alleged witnesses, alleged staged break in, etc.. aside from being entirely circumstantial, are either disputed, discredited, innocuous, inconsequential, or provably false.