I tagged the MalReynolds account on 9/21 and all that merit-giving started on 9/30. According to the
sales thread, he hadn't sold it as of 9/25 so my guess is that it changed hands shortly after MalReynold's last post there on that date and the new owner started selling merits or distributing them to his alt accounts and/or friends.
I'm not tagging merit abusers, but MalReynolds has already been negged for account selling. As to the members he gave merit to, it's a really tough call deciding whether they're alts or not and whether to give feedback. A person can't control who he receives merit from, and if all those accounts were to get tagged it might not be the right thing to do--unless they can be linked. So my guess is that everything that could be done has already been done.
Unfortunately, this is one of the negative effects of account sales, especially high-ranked ones with sMerits to give out.