Might be, but I can assure you there are some other deer around you with horns and bodies that size. Deer like that don't get that big in that area by being seen. We have them disappear all the time at our place and show up at some of the strangest times...usually during extended doe season
Don't give up hope on him, but it does suck to lose any of your bigger deer...really sucks to lose any deer to poachers.
Good luck to ya