Those are what I call wind checks. Where you hurryed the heating made the woods mositure excaped faster that the other parts of the wood. Once a check starts the excaping moisture keeps it going untill theres no more mosisture.
You'll also get those with age.
I've been working on a osage snake bow. The stave I've had for 22,23 years. It has some bad checks that go all the ways through in places.
I just reread your post. I've never worked with OCEAN SPRAY but all the white woods Iknow. If those are all the way through and you can see them in the bows back. It's likely done if you can't work around the checks. You might back it.