Your "leader" has and he has indicated that it was when I was involved with Nxt (which you would therefore have known if such a thing was true).
All that I can recall is that Nxt community was pissed off after you implemented AT on Qora. You were paid but returned the money, it's not worth to be called a scam IMO, especially taking into account that JLP didn't help you with the integration into the core. I don't know about other cases. Maybe ask David for the details?
I gave him one bitcoin directly for him to implement AT on NXT, and I was never refunded.