Update: This matter has become more interesting this week.
SBR is involved on my behalf. Full support.
Belief is that Betsoft did not inform MYB of any such "glitches". Betsoft has been silent (for now). SBR is working to connect with MYB Management to connect the dots and to determine if Betsoft was actually even involved in triggering "a request" for a "review" and subsequent seizure of the large balance. There are multiple other options to take for resolution purposes if MYB were to continue to avoid the matter and remain silent.
The easiest path for MYB is to place the balance back onto the account, re-enable the account for full access play/payout purposes, and to have the opportunity to self-promote the fact that a Player(s) has/have won big; whereby positive advertisement/feedback/PR occurs.
Stay tuned.