Strictly MOO - I don't know B, but judging by "oh Suzanne" plea, BM has some major histrionic traits. This, coupled with parochial views (that he may, ironically, not quite share, although he tries his best) might create certain inferiority, and one major complex. Think of it - besides money, what a man like BM might be thinking he is missing in life? He had a beautiful family. What else? It might be important in the context of the story.
Remember his interview with TD. He was boasting of his friend's military feats. What does it tell you? What else
would he love to boast, but can not? MOO
P.S. Strictly my idea. (I would have bought popcorn, but quarantine doesn't help as it is.) I think the motives would include money, BM's extreme moodiness that TD had noticed, and histrionic perception of aging self.