The Sohal seems to be breathing much faster than the number of ich spots it has would suggest that it should. to me, that implies multiple issues.
Blue light makes visual identification from photos and videos VERY difficult. White lights work much better.
Is this tank a FOWLR? You have a lot of fish in there and moving them all out to a quarantine tank seems like an impossible task to me. If you could find it, chloroquine to your DT might work, but I cannot find that drug now that it was pulled from the market due to Covid misuse.
You *might* be able to medicate the whole tank with copper, but all that rock is going to make it difficult to maintain a proper level. What about pulling most of the rock and sand, soaking it in FW and adding PVC pipe for the fish to hide and dosing with copper then?
What was your water temperature at before you raised it? Raising water temp is a way to manage FW ich, but it just makes velvet and marine ich propagate faster.
Jay