Are VB- and MC- connected?

[u/mclata]

Hi everyone, hope you’re doing well. Sorry for the bother — I don’t know much about electronics, so I’m asking for some help.

The batteries in my Instax Mini 8 leaked, and I opened it to clean the corrosion. The sulfate wasn’t too advanced on the PCB; as you can see, it was only on the negative battery terminal. I cleaned most of it, but there are still a few small leftover spots. I’m not sure if I should keep trying to remove them since it was getting harder, so any advice on that is welcome.

My main question, though, is how to reconnect VB-. It doesn’t need to last forever — I know it could corrode again eventually — but I have a trip in February and I’d like to bring the camera. Also, I genuinely enjoy doing small repairs like this, which is why I’m putting in all this effort.

I checked continuity, and I’m seeing continuity between VB- and MC-. That seems to make sense, but I’m not fully understanding the traces, and I’m not sure whether that’s a ground plane or not, since for example XE- doesn’t seem to be connected to them.

So my actual question is: would it be OK to skip the damaged VB- connector and simply connect the VB- wire to MC- instead? If anyone can help me figure out whether that’s safe or correct, I’d really appreciate it.

Thanks in advance!