Where’s the evidence the GOP has EVER been competent at vote fraud. The only example I know of is the last MS senate primary. They may well want to use it, but they’re not smart enough to use it effectively.
You're absolutely right. They engage more in using the levers of power at the state level to malign, marginalize, and badmouth their unchosen candidates.
As an example, a friend of mine in Florida says he gets three or four 4-color glossy campaign flyers in the mail each day from the RNC badmouthing Trump.
And while the RNC might not be agile enough to fraud the vote, I think unfriendly governors can definitely make a difference in the vote counts.