Forcing the liquids is good. Is this a vet you trust? If not, you might want to consider a second opinion if you can swing it financially. I would be concerned, too, that Scooter is not noticeably better by now. Eihter he doesn't have an infection, in which case he needs some other treatment, or the meds are not effective, and he needs a different antibiotic. He's been on the meds over a week now - he should have started feeling better the next day.

Sometimes they have to have their urethras flushed. I can't remember the name of the stuff they use, I think it may be Wohlper's or something like that, and it dissolves the crystals. It isn't a cure, it just resolves the current episode and makes them feel better. If he's an easygoing cat they can do it without anesthesia or with just sedation.

And if this a vet you trust, don't be shy about voicing doubts and bugging him.

If he's not eating because he doesn't feel good, try offering him some tasty table scraps - it won't hurt him. If he's not eating because he doesn't like the new food, try mixing it with his old and gradually increasing the ratio of the new food.