There is some level of compensation where our protagonist could have retired after his first paycheck. His paycheck was very high, but not that high. He made a bad career move, despite the pay. For some people it would have been ok. Experienced fighters would know how to take the hit better. For them it would not have been such a problem. In the story it was a big problem. I would say there was probably no level of compensation that would make it worthwhile for the character, given he had to keep doing it on a daily basis indefinitely. His old job was fine. His new job let him pay off his mortgage faster but made his whole life worse. What good is all this money if one's life is suffering? If money lets you buy your way out of suffering, that's good.
When I was younger one of my favorite punchlines was "What kind of (wo)man do you think I am?! ... Oh, we've already established that, we're just negotiating price"