Does not fit surefire g2x pro - American Defense Manufacturing Surefire 6P Offset Flashlight Mount

I purchased this for $25 on DVOR, I now know why it was marked down so far. On the website and even the pamphlet that comes with the light, it says it fits the G2X pro. However, the ring is too big to securely hold the G2X pro, even when cranked all the way down. Shame, because otherwise it seems to be a very solid, lightweight and low profile mount.