Not related to this particular reason for suspension, but I had a friend who's GCP account got put on pause a few weeks into his project because his payment method was flagged for suspicious behavior. This friend had an incident of stolen identity in the past 24 months which caused a lot of issues and basically any CC linked to him seemed to be problematic for GCP. Swapped CC linked to the account to his business partner and fixed everything.

Lesson: if you use a CC with GCP or cloud services, firewall it from everything else you do to be safe.