Corbett has that old time footwork and stance. Jones has no idea what that could do to a fighter. Also, Corbett was a physical specimen and he'd impose his will from the outside.
To be fair, Jones himself has the old school footwork and stance. It's really rare in the modern era seeing someone fast enough to get away with leaning back against an opponent. But Jones has the speed advantage and will, at some point, crush him with the left hook.
RJJ also has the glass chin that Corbett will take advantage of with his counterpunching and legendary skills
Whilst Jones has chin issues, I don't think they're any worse than Corbetts. Plus Jones is a bigger puncher, and he's quicker and less predictable so more likely to exploit the chin of Corbett. Both fighters were renowned for their skillset.
He beats Fitzsimmons and he has a chance to outpoint Jeffries, although he must avoid getting hit clean.
I'm not convinced there's much evidence Corbett had chin issues. The only time he was anything like KOed by a head punch was the first fight with Jeffries.