I've had a nice sit-down and have decided the reason listed for expulsion is too asinine to be the entire reason.
Either the snippet of conversation posted is presented out of context, or there was an underlying issue. Most likely candidate would be underperformance, since the "accused" couldn't talk about it directly so they just made up nonsense on the spot.
The fact that the conversation exists as a screenshot at all likely means the op went all the way to the point of adding someone on another server to their contacts, then harassed them when they were out of dungeon, demanding an explanation for why they were kicked.
Ultimately, at least two other people (perhaps three) simply didn't want the op in there, and no amount of tos or report fudgery would make them want to keep them around.
SE is powerless when a party doesn't want a player around, so take the L and move on.
Majority vote is a proper dismissal.