Not sure what do you mean by chat not working, but I do have a problem that the chat doesn’t refresh unless I restart the game, and not reconnect.
Ultimately, however, if you have swapped all these clans and you actually fail on 600k and below Alphas… your problem is not the chat, but the clans themselves. For example, I didn’t put any effort into my clan whatsoever. No recruitment, no straddling or wooing. Just folk who have joined and left at their own will, since it’s a public clan. About 10 are 2500-3500 and the other 10 are 2000-2500. On this 600k Alpha - at least 20 people participated before it went down, and some didn’t even do more than 1 try(though others did 4). Nobody was specifically coordinated via the chat, aside from a few messages like “better be active” and “do your best”.
Obviously my clan won’t be next to those that beat 1.5-2mil Alphas, where every member deals 100k+ damage over 24 hours. But I’m fairly sure that such “basic public approach” could very well do up to a million, that is - level 4-5 Alphas.
If you absolutely have no luck with clans - just start your own. It’s 50 runes, not 500. Kick inactive people, say something nice to those that participate, and you might just get started.