Highly likely someone has evidence that their 'stablecoin' is backed by thin air rather than actual dollars, which could be considered a minor bit of large scale fraud...
My very amateur guess is that Paxos sees stability issues with Binance and wants to cut ties, or they are getting too much regulatory scrutiny to make it worth it and are dropping them like a bad habit.
You say that as if it means something. Enron routinely passed audits from a Big 4 company.