I want to be able to use drawbridges in my griefprevention claim, to do this i need to /trust the playername of the person placing the blocks, what's the fake playername for drawbridges?

Out don't need a fake player to place blocks. The drawbridge likely places it using the world and no player

Drawbridges placed by the player cannot build in said player's claim using the plugin Griefprevention, is there a way around this?

It appears that the fake player name is Player.Drawbridge