Does this look like velvet ?

I’m not sure if it’s velvet or just his natural iridescence? I’ve been treating him for a bacterial fungal infection this whole time. Could he have had velvet all along?

It's possible. Shine a torch on the fish after lights out and see if there is a yellow/ gold sheen. You can also photograph the fish after dark and the camera flash will do the same thing.

You can treat velvet by raising the water temperature to 30C for a couple of weeks. If you don't have live plants, turn the tank light off during this time. And you can add 2 heaped tablespoons of salt for every 20 litres (5 gallon) of tank water during this time.

Before you raise the temperature, wipe the inside of the glass down and then do a 80-90% water change and gravel clean the substrate. Make sure any new water is free of chlorine/ chloramine before it's added to the tank.

Clean the filter if it hasn't been done in the last 2 weeks. Wash filter media/ materials in a bucket of tank water and re-use the media. Tip the bucket of dirty water on the garden/ lawn.