After Microsoft flirted with acquiring Intuit, then shortly thereafter released Money to compete directly with Quicken, I assume all due diligence is just a way to hoover up intel.
To inform a buy vs build decision. To better validate market assumptions. To identify key contributors and poach them.
Whatever.
No earnest money? Fine. They clearly were going to drain my blood and powder my bones. Their prerogative. But they can proceed to kill me and my product without my help.