We usually refer to "stress cracks" in vintage bows as those cracks that run lengthwise with the limb instead of across the limb like your "crease".
It looks to me like something has been dropped on that limb or its been compressed in some way. It may just be where a spring arm type quiver has compressed the finish in that spot over time.
If the glass is damaged, fibers will likely lift on each side of the damaged area or you may see stress cracks running out from the crease.
Not sure I'd want to be tied to that one at full draw, especially if the "crease" is on the back of the bow.
Trap