This is silly. An obvious alternate is the Biden administration wants to keep Ukraine from being defeated.
Another obvious alternative is the Biden administration wants to give incoming President Trump another bargaining chip to help end the war.
A strong alternate motivation would be for Jill and Joe Biden to further fracture and destroy their enemies who betrayed them when they ousted Joe Biden, by helping a President Trump destroy the Democratic party.
The Bidens are thoroughly corrupt, self-serving, mean, and vengeful. May be they have been offered a deal - help Trump and avoid prosecution.
Defending Biden is really sad.