I think delamination is the wrong term to use for such a crack. Those aren't delams. A bow can only DElaminate if its first been laminated, imo. To me they look like regular drying checks.
Staves can get drying checks anywhere. Back, belly, ends, or sides. If they do get drying checks, WHERE they get them depends on other factors like wood type, whether the bark and sapwood was left on, how, how quickly they were dried, width and thickness while it dried, and more. I've seen perfectly good, beautiful staves, left with the bark on and dried too quickly acquire drying checks just like yours, while others from the same log, that instead had the bark, sapwood, and excess width and belly wood removed earlier, and dried more slowly, were perfectly fine.
I wouldn't make a bow with even one of those checks in it. If I can remove all of it, fine, I'll use it. If there are too many or one is in a real bad spot and can't be removed without ruining it for use as bow wood, I'd burn it. If it was one I paid for, I'd get reimbursed.