we know fang is the last dlc but do we know when is the last patch for the whole game?
No, we don’t.
Fangs is the last expansion, but not the last DLC. There will be another Loyalist Pack DLC.
As for game patches, Crate will likely never announce such a thing. For one, they have no way of knowing how much longer they need to support the game.
Also another dungeon supposely. This made me laugh. Patches will be coming out for quite some time as they fix stuff. Do balances etc. one thing about crate is they do fix things.