I know there are folks offering this as a service now, and drones are illegal to use in attempting to kill a deer. If I understand it right, if the drone finds the deer and it is not dead, the hunter cannot then slip in and finish the deer off during the over night period, but can recover a deer found deceased this way. I think they have to leave it alone if it is decided to not be a fatal injury, and there may be a chance the next day to slip into the area the deer was marked to verify and or recover the next day. Not certain on what the ethics of the later are, but recovering one that is dead already I think is a good thing.