Correction: Biden will have a VP picked for him. He's in no condition to do the picking. Even if he imagined that he could make the pick himself, the DNC puppeteers would have no trouble convincing him that the person he picked "declined", and they would have no trouble convincing (with cash and/or threats) the person he picked to STFU about the fact that he tried to pick her and she would have loved to accept but the DNC puppeteers wouldn't allow it.