I suppose the reason I initially posted this in tech support was because I wasn't sure what to do about it. I didn't want to use the RMT reporting function, since the message didn't advertise RMT, and I would have had to click the link to confirm anything. That's a hard nope. The last thing I need is to get hit with a ban or something for abusing the RMT reporting function. But if I just put it in general chat, I'm doubtful that it will generate any kind of official investigation into the account(s) which have been hijacked to send out the shady PMs.