My bet is against the critters being coyotes, and instead being some mix of coyotes and dogs.
Coyotes have made a big comeback in this part of the world in recent years. Particularly in Ohio. A guy even caught one in a very urbanized Pittsburgh neighborhood about a mile from downtown.
Coyote-Wolf Hybrids Have Spread Across U.S. East
They are a lot bigger and badder than the Western Coyote.
I agree. Coyotes attack small vulnerable things, but a man on a lawnmower? Not unless he was near their den or something.
Rabies isn't all that common in OH. That might explain irrational attacks, if there were rabies. It's a mild autumn in OH. I can't imagine finding food or shelter is a problem.
It's an odd story.