HI ! WELCOME to PETTALK JELLICOE !!!

If I were you , I would go back to your vet and ask to give the antbiotics in shots ! MY RB-cat Sydney was also unwilling to take pills ; he once needed anti-biotics too . The only way to give it to him was with a shot ! So had to go to the vet EVERY day for a week ; but I was happy to do so!! He got better!!
I was also once told that there exists a little instrument to "shoot" the pill right into a cat's mouth . Ask your vet , he will help you !

Success !! And keep us updated , okay ? We all care very much here at PT !!!