*GAG* well not sure how to help you, never hatched eggs before just was seeing if I could help ya, it might fix itself but unless you get some help then might have to just let the quail help itself or just let nature take over, I wouldn't want nature to take over but sometimes its all you can do, tell me if he/she makes it, hope he/she does
You could try holding the egg shell down and let the chick pull it on it's own. If it's yellow it's more than likely not vascular so pulling it or cutting it should be okay, just use clean utensils. If you go the pulling route do not pull it off the chick, but rather pull it out of the egg.
In case of bleeding, have something nearby to aid in clotting, cornstarch works wonders. After it scabs over treat it with iodine.