Well, based on these chat logs you've had the problem player with you all the time.
It is the person called REM.
When I GM my players have a ton of freedom, they can play pretty much whatever they like. e.g. I allow evil alignments, but they need to give me a really good motivation why they are working together with the other players. That being said:
I don't allow people playing a**holes just for the sake of being a**holes because it can be very disruptive. Sounds like that was REM is doing, hiding behind a "perceived high IQ character". And to me it doesn't seem REM has any experience with high IQ in reality. I'm actually a member of Mensa and we happen to understand that this is not something to be proud of, because that is just how nature made us. Being condescending to others is honestly a trait I have yet to encounter in any of our members.
The TL;DR; REM is playing is an a**hole and his logic for why he is an a**hole is completely flawed on top of that.
Casting Charm Person on a party member is absolute rubbish. It is a hostile spell. You might as well cast a damaging spell on your party, that's player vs. player combat.
Under normal circumstance everyone should be coming to a game to have fun, and if a player is making it hard for the others to have fun, I'll have a word with them. If that doesn't help, they may have to be let go.
This probably doesn't help you too much since from my understanding you're not the GM. REM and ARM need to sort this out themselves, out of game. If they can't, the GM might need to take a decision that what one of them will not like.
