Who does the actual auditing? Can the Midwestern state legislatures demand that the auditors be independent? Out of state auditors would be helpful.
Maybe the state legislatures could since they are the ones who should choose electors, but do you see any state wanting someone from out-of-state when there are probably plenty of their own people in-state? I think it comes down to volunteer observers within the state; and they aren’t actual auditors if I understand correctly. Unfortunately, I don’t know enough of the details.