As I mentioned, this is normal for a kitten getting its adult teeth. Unfortunately, vets are only given minimal education when it comes to dental health. They should have all their adult teeth between 6 and 9 months. If the bad breath continues after this time I would then be concerned.
I had never heard of a Torbie. This is my 4 yr old rescue named Isis. She's very sweet but vocal. Her belly has cream color with brown spots and her sides are marbled if you can't tell from the photo. Is she a torbie?
Kittens always have bad breath when their losing their primaries and their adult teeth are growing in. The ulcers may be a result of the fever from infection. I would give them time to heal. If the halitosis continues after all adult teeth are in, get their kidneys checked, not through...