The whole idea of the bond is that it covered the full amount of the judgment and is held in escrow, and would be turned over to the state when Trump loses his appeal. And it’s up to the bond issuer to make sure they have collateral enough from Trump to cover that bond (and full judgement ) should they need to pay up.
The bond issuer not having the collateral to even cover the $175m, let alone the nearly $500m that would be due if he loses his appeal is the whole issue James raised with this bond to begin with (well and the fact that they didn’t have the right certification to even issue a bond in NY).