So we know that Hussein issued orders for Shokin to be fired. Biden just carried out orders. So Hussein had moar to lose than exposing Hunter Biden's corruption into Burisma.
Obama Admin Strong Armed Ukraine NOT To Investigate the leader of a non-profit in Ukraine known as the Anti-Corruption Action Centre (AntAC) which was under the scrutiny of Ukraine prosecutors as a part of a larger probe and backed ‘Mega-Donor’ George Soros.
So I looked up AnTAc site and found this guy, Francis Fukuyama who has quite a resume
Chicago
Stanford
Yale
Harvard
Telluride House
https://www.washingtonexaminer.com/news/joe-biden-visited-ukraine-six-times-in-eight-years-while-vice-president
https://bigleaguepolitics.com/flashback-obama-administration-pressured-ukraine-to-drop-investigation-of-george-soros-group-in-2016/
https://www.americanlibertyreport.com/articles/obama-admin-strong-armed-ukraine-not-to-investigate-mega-donor-george-soros/