There seem to be some false positivies, like RobbaN claims he encountered it once and because he didn't know what it was, he thought it could be a bug with the Faceit AC or such so he muted his mic and didn't speak to his team for the full map. They lost the map 1-16 so to me this checks out. Next map it was fixed.
The next day he got the bug again and he contacted the admin and disclosed everything about the bug, and he's appearently got screenshots to prove that.
I mean, if his own story is to be believed he shouldn't be banned. But there's no real proof to what he's saying, since I doubt there are TS records from back then and even if there were, there's nothing to prove that he wasn't talking to them outside of TS, such as being in the same room.
I don't think any of these false positives could be unbanned without proper proof, but I think we should still acknowledge that there might be a few times when the ban isn't fully justified.