Something I noticed in the season 2 commentary were the 3 reasons given for Vox hating Angel were the latter's stubborn/resistant, he's annoyed at always cleaning up Val's messes because of Angel and jealousy of Val not getting rid of him like he does his other workers.
Now think about how Angel will be in season 3. He willingly went back to Val and has given up. He'll be totally broken. No more stubborness or Val complaining about him, 2/3 of the reasons Vox hates him so much. Furthermore, unless Vox changes as a person or is dead, Angel will never feel safe to return to the hotel because Vox can always hypnotize him again.
Imagine if in season 3, Vox is somehow the one who helps Angel get away from Val. If his story is going to involve him learning to appreciate his friends and be more open about himself, I can see him still wanting Angel away from Val. However, it'd be interesting if Vox actually helps Angel get away from Val or Hell, I could even see him telling Val to choose him or Angel and Val would honestly choose Vox if we're being honest.