FS and Folk are different sports. We both have seen guys who excelled at FS but who never really did jack at Folk, and vice-versa. Carter Young is a classic example, beat Gross in FS, but has never even made R12 at NCAAs. Not only that but the maxim is that freshman struggle on bottom. That's not always true, but a lot of the time it is. So a FS kid in his first year of Folk could seriously struggle on bottom. Theoretically it's an easy fix if the guy you are teaching is smart and adaptive. Standups nearly always work if you are fast enough, for example, and Ono is pretty damned quick, as I recall.
I agree that Ono would likely place at 133, but I'm not sold on his mat work, at least not until I see him go under a good rider. I've seen too many FS guys get pulled apart like wishbones in folk competition to automatically assume they'd do as well in folk as FS.