I can save you time. There is no debt to be repaid. There's also a group who already tried to sue, a year ago, who gave up because their lawyers said there was no case, the same as my lawyers said a year ago too.
I would find it unlikely that a group "tied to sue", but didn't because "their lawyers said there was no case", and you, as a defendant would know these facts. A defendant would not typically be privy to conversations between someone who is suing you and their lawyers, and I cannot imagine a situation in which you would know that a group of people was considering suing you but ending up not doing so on the advice of their lawyers.
This sounds like you are blowing smoke to me.