I don't get that move on two levels:

1. Cumala is going to go up against the pagentry of the office, a speech,which will be just like a State of the Union address, right after a fireworks display over the Washington Monument. That will cast her as the loser that she is.
2. Attacking the other party right after their address is generally not done during conventions.

But whatever, act like sore losers, losers. Your numbers will crumble even more.