If you can’t put weight on the front foot during the throwing motion, you’re not going to have good mechanics. And for a QB, it’s all about footwork........Whatever
Actually, an athletic QB with good arm motion skills can throw even with a sore ankle. Of course, the velocity will be impacted.
Tua lacks basic/proper athletic throwing skills/arm motion and, unless he develops quality throwing skills, he'll never make it as a passing NFL QB.
Tua's just a new version of Tim Tebow - an athlete but not an athletic passing QB.