The first thing he did when offered the Joshua fight was to call PFL, and they were OK with it.Lol the UFC were right at the end, he was never coming back after he tasted that bag so it didn't make sense for the UFC to agree to that.
Ngannou conned PFL
How did they get conned? He is on their roster, giving them massive visibility. And he does not cost them anything.
They would be worse off making him fight a random HW, where they would have to pay millions in purses (Ngannou + 2mimlions for the other guy) with a guaranteed net loss.