Yes it a Macrodactyla Doreensis. I gave it a cup for its foot as you've recommend and it settled smoothly. It's in a specimen tank by itself and the rockwork I prepared for it seems to make a nest that it has approved of (so far). It is reacting sticky, accepting food, although it is slightly bleached but not too badly. It's foot is way-way too pale, more or less same colour as the disk and and skirts.
I noticed first one, then two of these small tiny dots.
It took some time before I realised that they were inside the tissue and not outside it, but they move everywhere, including up into the tentacles and are clearly just hanging out in there.
They seem like a sand spec, with a tiny tail or something.
The video is of the biggest one I have seen, and appears to have a tail almost like a crustacean?
I could see three today at the same time, so it has at least three of them, but none of those I saw today was the bigger one from the video. Perhaps it has left the anemone.
Thank you so much for the recommendation of the pesticide, I was very worried that I would have to see the anemone be eaten alive by some pest.
It's amazing that so much can be going on inside our pet anemones, thank you soooo much for helping me clarify this Minh, I really appreciate it and clear answers in the hobby can still be really hard to come by.