It seems highly unlikely that Silvergate would be willing to accept 129,000 BTC as repayment for the 205M USD loan that Microstrategy took out. There's not enough liquidity on the order book for Silvergate to liquidate that entire position to get back USD (this is looking at current liquidity, which would suffer even further if BTC fell more). Thus it seems much more likely that the actual price where liquidation would happen is much higher, since Silvergate needs repayment in USD, not BTC.