That's so bad poor lil hammy
. Idk if I'm right but that watery thing looks like eye discharge to me. I wonder why the medicine is not working, maybe the root cause is different?? The discharge is a sign of eye infection, recently my 1.5 year old hamster had such case and I treated it with enrofloxacin and he took a whole month to recover ,umm id like to know the antibiotic composition if possible . Overall his appearance is still fine ,the fur may look greasy during this stage because of a few reasons : if hammy is not grooming or the weakness makes him look like that,if he's still eating on his own there's still a way out !!
I would suggest taking him to another vet because otherwise the condition may get worse. I hope the best for you ,pls recover soon Moss.