Just noting that the side channel conversation carried on for almost an hour, if I remember correctly. The user in question had mentioned potentially overdosing on tylenol. It's obviously a very heavy topic they introduced, and I'm not comfortable with them entering the chat again until they've dealt with it. The racism and the suicide threat are, as far as I know, the extent of their chat presence in 19.
I'm not sure about a ban, but I'm not okay with how they made several other members of the chat feel. The fact that they kept pushing the matter also doesn't sit well with me.
Edit: Okay, how about this. Ops in 19, if he ever shows up, take him aside and make sure he's dealt with the suicide issue. If not, kickban. Given that he didn't seem to listen to anyone on chat and only made everyone uncomfortable, I don't see any reason for letting him back in until he's dealt with the pertinent issue, troll or not.