I have no inside knowledge of if he left, when he left, what paperwork was/wasn't filed, but I can say for certain a couple things
No coach worth their weight in anything would allow someone who missed a huge chunk of pre-season workouts, essentially quitting on their teammates, to play without some type of suspension (if you let them back at all).
So let's say Buzz says he has to serve a 10-game suspension...that would bring Sy back for the Kentucky game, some mid-majors and then Syracuse, UVA and Pitt
School would start back the following week and Sy would be academically ineligible for the second semester. So if you're Buzz, do you really set a precedent for a kid who quit on the team and would only be able to help in 5ish meaningful games? If you're Khadim Sy, do you sit around on basically a 1-year suspension in a situation you weren't completely bought into in the first place?
I'd put the odds at 99.9% that you don't see Sy at all this season, and around 90% that he never plays another minute at VT