I think you'll want to see it in person. Under heavy actinic light, the red haddoni look darker than under normal light. Based on its sideways position, which I assume is because it is still acclimating, I would be concerned of its overall condition, which is why you'd want to see it for yourself. Hopefully by the time you see it, it will have dug its foot into the sand, which is a sign that it has energy. IME red haddoni are a lot harder to acclimate than other haddoni. I've had two die while other haddoni did fine. Not sure why this is -- could be that they are collected farther out and are therefore are in less than optimum conditions for longer, and when we get them they are in worse shape, just a guess.
It's hard to tell in the photo what the other two nems are. Could be haddoni or gigantea.