This is not correct. They used those bitcoins to try to defend the peg. Here you can see the actual treasury: https://datastudio.google.com/u/0/reporting/b31cc9e5-c54c-44...
My understanding is that its more likely that they were allowing connected insiders to cash out at face value rather than "trying to defend the peg" at the prevailing market rates.
But yeah, I'll be surprised if Do Kwon doesn't end up sitting in front of a judge