Landlord
Banned
Before you go too far into that strength of schedule argument, look at Hackenburg's numbers against Kent State.
13/35 (37.1%) for 176 yards
I understand he could be a great talent and have a ton of potential, I think he's a little overrated at this point in his career based on what he's done on the field.
How about his numbers against UCF, which both obscure quarterbacks you listed also played against

Hackenberg - 21/28 (75%) for 262 yards, 1 TD, 0 INT
O'Korn - 24/46 (52%) for 231 yards, 1 TD, 2 INT
Walker - 26/44 (59%) for 382 yards, 4 TD, 1 INT