He seems to calling for a criminal investigation—more consequential than a gaggle of out-of-power legislators honking about perceived corruption.
This.
An independent investigation is needed - to hold the Biden's accountable, or clear them of wrongdoing altogether.
This cloud over the head of Democracy can't be allowed to continue.
Clearing up the charges would help Biden Senior. It would help Biden the Younger too - especially if he intends to run for president himself.