Fish are most vulnerable when they get spook or stressed like that. I lost a beautiful Powder Blue that I had for a long time when I consolidate and move tanks. I lost a Purple Tang when I do major tank clean once also. I have lost other fish to the carpet but it is because these fish were dumb. Those two were my mistakes. The expensive fish are the ones that hurt also. I have learn to take the anemone out first. Put is separate container, even Magnifica. Some Haddoni I cannot remove unless I removed most of the sand around him, I but a basket on him and weight it down with a rock to protect fish from him when I move tanks, or do major cleaning.
BTW, my Foxface is a smart fish and have not been stung by my carpet even once. My Atlantic Blue is another mater. He have been stung by my carpet multiple time, more than one I thought that he was a goner. He seem fine after a week or two. Blister up, loosing scales and they just grow back. That fish, IMO, is a dumb fish. I may be too rash in my judgment. It is possible that because there is no Gigantea or Haddoni in the Atlantic so it was never programed into him to avoid them.