Someone pointed me in the direction of this thread, and I checked mine out. I have the DT Swiss shock, and have had the bike for over 3 years (I think…just after they were first released anyway!). I've never had a problem with it bottoming out. I run about 10mm of sag, which fits right in the middle of the range recommended by DT Swiss.
I guess it's a problem with the Monarch shock not working the same as the DT Swiss (which the frame was allegedly designed around).