He's spent 20 years fighting a war
Which he had no right to get involved in.
trying to protect those poor Phaedans from being slaughtered when he could have hidden behind the PD and stayed on Enterprise drinking coffee, working his way to Admiral.
Stealing Enterprise and making that deal seems to be his last & only hope to win.
That's his problem. Stealing a Starfleet vessel is theft. Breaking the Prime Directive is a gross violation of Federation law.