another thing i was training a pupil just like you that ate,& ate but couldn't gain a pound,he was actually loosing weight.after running some tests we discovered he has type 2 diabietes,and his blood sugar was over 400,(normal range is 80-120),i would suggesting buying a Glucose monitor about $19.00 and testing your blood sugar,or go to the Dr and get some bloodwork done, this will tell where the problem lies,it could even be something like a hyperactive thyroid.
I doubt it its a medical problem. I bet you youll find the problem when he says his diet and training routine. Im assuming your Gear is fake