Hi, just seeing your post now. I can't say what happened to the cleaner wrasse, how long did you have it, they are very delicate.
Do you have invertebrates in the tank? If so, are they doing o.k.? If not, you'll need to check for water quality issues. If the invertebrates are all fine (I think I see an anemone in one picture) then you can focus more towards fish disease issues. Of the medications you have, the first two are for protozoan issues and to be honest, would not be something I would use, even for that. The EM Erythromycin is an antibiotic, and the lesion on the clownfish does seem to be a bacterial issue, so you could try using that in the treatment tank, not your display. It does look like in a couple of pictures, one of the clowns is swimming head down. If so, that is not a good sign at all, it means the fish is on its way out and the antibiotic won't likely have time to work - sorry!
Jay