The wound looks awfully ragged to try to seal with super glue. What I have to recommend is pretty complicated, but we'll see how it goes over.
The crop is double-skinned, meaning it has two separate layers of skin. You need to maneuver the exterior wound and look at what the inside wound looks like. Measure how big if it's not the same size as the exterior.
I would debride and trim away the ragged, necrotic edges of the exterior wound and the feathers an inch away from the wound. Instead of trying to super glue it, I would place a compress bandage on the wound after spraying Vetericyn and the ointment smoothed on. Then wrap with Vetrap around the wound and on his back and under his wings. It's important to wrap loosely enough so the crop isn't restricted and compressed. But you want the stretch bandage to be snug enough it'll stay on.
It concerns me that the wound has such jagged edges and I believe the wound would knit together better with the wound cleaned up and streamlined.
I've tried suturing a chicken before, but the skin is so thin, the stitches tore loose. It doesn't appear the wound is closing on its own. This is why I'd like a report on the inner skin layer to see if it's closed.