Yeah I'm not sure how much validity there is to this, usually MMO customer service tools allow notes to be attached to petitions but not players - its too open to GM abuse if they start letting them attach random notes to players. Customer service turnover is always high in these type of industries. I suppose a GM could leave a petition open on your account with "this is a multiboxer", but again, wide open to abuse - botters would "report" themselves as MB'rs and then go ahead and bot away, assuming that GMs will just ignore bot reports.

Random GMs also don't follow up botting reports, they first run software checks to see if you have known bot software, if not only a handful of GMs follow up on bot reports (those who know how to spot them etc) and I'm sure all of them know about multiboxing. Its pretty obvious if a GM spawns invisibly by you that you are multiboxing and not botting if your 70 is pulling stuff and AOEing or if your main is quest killing while the others are on follow.