Illness/Sickness: Tiger's eye turned black please help

[walhofkn]

Hi! I just got back from a two week vacation and I had left my tiger salamander in the care of my grandpa. To my horror, I discovered one of his eyes has turned black and he doesn't seem to be able to see out of it. I tried to run some water over it but that just caused him to keep it squeezed shut. His other eye, although in much better condition, also looks a bit foggy and has some goop around the outside (neither of these were present when I left). I had been getting calls from my grandpa with updates as to how it was going and I know for sure that my salamander has been getting enough food and water. I checked around in his dirt (currently topsoil) to see if there was anything weird and I did discover some odd white plant-like things which I don't know what they are (pic below). My tiger had previously had coconut fiber instead and had also had a previous case of odd goop around his eyes (nowhere near as bad and no fogginess or blackness). I took him to the vet and they treated it as an infection and told me to give him the medicine until his eyes cleared up and then to switch his dirt afterwards. I changed it to topsoil after his eyes had improved a bit and now this happened. Should I switch it back to coconut fiber? Could the white things be what is causing this? What should I do about his eyes??
Thanks so much for helping :happy:
black eye:

other eye:


weird white stuff:

 

[Otterwoman]

Are those white things worms?
If he was fine on coco fiber, I would switch back to that. BUt I think another vet trip is in order.