Possible ban?

[Bourne_Endeavor]

That's name shaming and reportable.

Not sure about the FC not being ban for announcing it, or at least the player doing it, SE does not like public denunciation, even if it's deserved :/ (which is, in some cases, such a shame cause some people would deserve to be named regarding some attitude we can see in PF....)

You probably won't be banned but, by doing it and tralking about it on the forum, it might be hard for you to find a new FC cause people might see you as a thief and bad reputation tend to stick on people ^^"

Depends. If said FC announced it in PF or typed up something like "this <insert cursing here> thief..." etc, then yes, they might get into trouble. If they simply warned future FCs this person joins, they wouldn't. I've also heard GMs will step in if people have an agreement in chat and one tries to run off with free gill/items.