Why would Mark Scout ever go back to Lumon after the events of season one?

I can’t think of a single satisfying answer as to why Mark Scout would ever return to Lumon after the events of season one. He spent the entire season skeptical, and on the verge of quitting. Surely his sister telling him the things Mark S. told her would drive him even farther away.

Him choosing to send his innie back to work seems incredibly against everything we saw in season one.

I am curious to hear some ideas and theories that you think would be a satisfying answer to justify his actions! If you were a writer on the show, how would you do it and what reason would you give for his return to Lumon?