In very short- they did a lot.of shit to him, treated him like garbage the entire way, and then at the very end they literally tried to bribe him into being the scapegoat for the backlash they intentionally caused.
It's interesting, how the game direction Hugo Martin tried to delay and sabotage him, the big reason he got the contract is he wrote to Bethesda higher ups directly, and as he did an exceptional ost for doom '16, they put him on the project.
Bethesda does a lot of questionable things, but this was probably their best decision.
Idk how involved he was with it, but I heard he contributed to atomic hearts music (this is when I decided to look it up, so expect to read an update below this in an edit soon, unless I get distracted)
Edit: there were 3 composers for the OST, he was one of them.