I think Blue guy has made some progress today. He's still swimming, eating, and curious, but his fins are still clamped up. They look like they were dipped in paste and got stuck together and look brittle or rigid like they're plastic. Here's a horrible quality video but you can kind of see how his fins are moving, especially at 29-40 seconds. The water is green from the fungus medicine.
Here's how he's looking.
This was the best I could get with a flash to check for velvet. In a way he had a shine to him with light on him, but I haven't come across an actual picture of velvet to really know what it looks like. The camera flash I think exaggerated the color in the picture anyway.
And this was the best I could get (my phone doesn't seem to like the green water, it doesn't want to focus) to figure out if his eyes are bulgy. They aren't cloudy at all.