Likely no timetable because they're evaluating the severity and the treatment options. But agreed that if this is a long-term thing, a redshirt may be the best way to go. Not a good idea to rush him back and risk re-injury.
You have to feel terrible for him, another setback in an already challenging year for him. So tough as a freshman to come in with all of the tumult, encounter setbacks in your own performance growth, then get hit with a significant injury. If he does redshirt, I hope him and Hurley commit to an offseason development plan and he comes back next year with a fresh start. He seems like a great kid with an extraordinary work ethic.