Right so this isn't really my area (I'm more shadow people, Whitby coast, that sort of thing) but big cat sightings are genuinely one of the better-documented cryptid-adjacent phenomena out there. The UK has decades of solid eyewitness reports and some decent plaster cast evidence for large felids that shouldn't exist here either.
The Ozarks thing doesn't surprise me at all. You've got dense woodland, plenty of prey, and not a huge amount of people actively looking. The German Shepherd size comparison is interesting because that keeps coming up in British reports too - people almost always reach for a large dog as the reference point before they clock the movement is completely wrong.
My question would be - what's the gait like when you see it? Cats move nothing like dogs and that's usually what convinces people they weren't just looking at a misidentified domestic or a coyote. Anyone got footage or even photos? Even blurry trail cam stuff would be worth posting up.