The MVMA instructions is for adhered concrete masonry veneer, not stone. Your pictures sure look like it's adhered concrete masonry veneer and not real stone. The cracks don't look like it has anything to do with supports. If it is adhered concrete masonry veneer, think of it as a stucco-coated wall with thin slabs of preformed stucco stuck into it. That and the rules for stucco and the MVMA instructions will likely point to the cause of the cracks.