The eye could have been caused by the fish being kept in dirty water, either at the shop or during the shipping (which the fish would then be shipped in that same dirty display/holding tank water). I would continue FW dips and immediately start Erythromycin. This has worked with fish that I have had look like that in the past. If it is indeed eating, that is a huge plus. A healthy Blueline should eat within a couple days of arriving, they are pigs IME. Take it slow and don't get crazy trying every medication available. So at this point: FW DIP + run antibiotic Erythromycin. After first antibiotic treatment is completed, and if the fish is eating, try Prazi/Metro treatment. I would only use Formalin as a last result or as a short bath. Maybe run some CP later if ich is present.
I must say though, i have brought back fish to full health that have looked way worse. You may be able to save this fish if it continues to feed well, in addition to proper medication.
