I guess the biggest problem with that theory is that it would mean all those individual county officials all over Ohio had to coordinate with the Trump campaign to allow access to the voting machines. That doesn’t seem possible, since Trump had no competent people working for him except Bannon and Manafort, and a conspiracy on that level would have brought out at least a couple whistleblowers. Especially when things turned out so badly after Trump was elected. All you would need would be one county official somewhere in Ohio who was also a farmer, whose livelihood was threatened by Trump’s tariffs, and the whole thing would come out in public. It’s possible, but it feels like a long shot to me.
But since then I have seen a lot of credible reporting to suggest that our voting machines are still extremely vulnerable, and plenty of foreign entities have plans to target them. It’s a thing to be very worried about for 2020, whether or not it actually happened the last time.