That's a good idea SiCrane, but my boss won't let me do that because their big thing is to conserve memory along with quick load times.

Thank you everyone for your help. Because of the nature of how the rotations work, I can at least keep acurate rotations around the z, simply because it is the last to rotate in both orders and therefore not scewed.

If you just have a start and a finish rotation matrix, there's no way to recover OR encode the number of complete revolutions between them. So not only can you not get those values back, they're meaningless because they will be lost when you create the new rotation matrix.