Have you actually gone around with a long level to check that these walls are out of plumb?
Lateral (sideways) thrust from a roof tends to show as horizontal cracks not vertical. The bond of the wall prevents vertical cracks, and for 6" concrete blocks to crack vertically is very unusual for anything except foundation movement
BTW, if you are installing tie joists at that length, they will need one or two binders and maybe timber hangers dropped from the rafters