Impossible to thread / unusable - Aero Precision VG6 Precision Delta 556 Muzzle Device

I should have known when buying this on a final sale, but this is absolute garbage. Like another user, I tried this on 2 barrels to be sure. The threads around the pin hole are so coarse the difference can be felt with a pinky tip. They are beyond saving. My only hope is to contact OpticsPlanet and see if there is anything they can do... but it seems unlikely given the 'final sale' notice.