He came back from his back injury to play last year, then proceeded to play most of the year with, I believe a fracture in his foot. He shut it down late in the year to have surgery on that.
The foot surgery could be a reason for a poor combine.
He didn't have a very good season last year and part of the reason for that was the new QB struggled.
Dabo Swinney his college HC has said that Ross will be a star in the NFL. I'd try and sign him if I'm a GM, the worst that happens is he spends a year on IR and never recovers enough to play. No wasted draft pick, no expensive salary, seems like a no risk move to me.