You're likely correct, but if I was a republican I wouldn't put all of my chips on Trump's compliance. He might just decide that he actually does know something, which would be even worse than republican hegemony.

I suspect that the other reason they put up with the fraud is out of self preservation. If Trump gets elected they might be able to keep their merry band of white supremists, war mongers, anarchists, bible thumpers, anti-science fools, etc. together for just a little longer.  If Trump fails the whole fraudulent facade blows apart.