Isn't it time for us to inform everyone (if needed then PM) and ask them to stop promoting/endorsing cloudbet? I have seen in the past when we smell anything wrong then DTs stepped forward and warned the users. If they denied then they tagged them.
Giving them a warning would do, campaign participants are not even part of the main operation of the gambling site they are promoting. Their only job here is to promote the gambling site and they are not the ones who are handling the payments of the gamblers, so tagging them right away because they are just wearing their signature would only ruin their personal reputation here in the forum. If you would really like to be notice I think tagging them first is ideal to get their attention on removing their signature, if they proceed on removing their sig code without any complaints then you can remove your tag when things clear out.