Out of Kilter Question

about three weeks ago I felt a painful strain in the very lower portion of my back (just above the tailbone) doing a 1RM Squat. I was in the third phase of the White Men Can Jump routine. After letting it rest for a week it felt strong again, and so I went back to the routine only for the soreness to come back. Now it is nagging and won’t go away. After reading out of kilter II I think that it may do to the quad dominance of that routine, and due to an imbalance in strength as well as tight hips.

My question, after all that babble, is if anyone thinks that part II of Ian Kings limping routine (which is hip and hamstring dominant) would be a good rehabilative routine for my back.

I tried squatting after a week of rest this past sunday, and felt the pain in my lower back on a warm-up set of 95lbs. I hurt it squatting 355, which I have lifted before the injury.