As for Bones, I also presume Phil is a normal human who is subject to prideful spite from time to time and he certainly wouldn't be the only person on the planet to stiff someone when a relationship fell apart.
I think the stiffing was the
cause of the breakup, not a byproduct. I haven't gotten to that part of the book yet but others have, and I think Bones was owed about a million dollars (mainly from the FedExCup bonuses) in back pay, and Phil wasn't paying for a long time, so Bones ended the relationship. I also think I heard Phil may have paid a portion (like $400k, and then maybe another $500k), but was still a few thousand to hundred thousand short.