Not head of 'election integrity', they're the subject matter expert on election integrity, working to destroy all election integrity for the benefit of the RNC.
Like if Sony had a head of piracy. They wouldn't be a pirate, but they'd know about pirates, and would be working to destroy, imprison, and fight actual digital pirates. For the benefit of Sony.
The goal is to create chaos, so that when Trump declare himself the victor on election night (which he will, no matter what the results will look like) it seems credulous to his base.
Then lawsuits will follow, with possibly some state legislatures declaring Trump the winner despite him actually losing the vote in their state.
Pretty much this. They realized that all they have to do is say they won, and get enough people to either earnestly believe it, or at least go along with it. Then, you can challenge literally anything the winning legislation does, regardless. You can say "well our election integrity committee found that blah blah blah mail-in ballots" or whatever - this is what they did in 2020 with the "suitcases full of fake ballots" thing in Arizona.