Ah, I'm sorry to hear this
However, I have treated many rabbit abscesses in the past, and almost all successful, so please be hopeful
I question how savvy your vet is to have given Baytril for an abscess, because it doesn't penetrate the abscess capsule and therefore will not help long term to eradicate the abscess.
There are a couple of good articles here:
http://www.rabbitwelfare.co.uk/resources/content/info-sheets/abscesses.htm
http://rabbit.org/abcesses-in-rabbits/
There are two primary ways to treat an abscess, in my experience:
1. To surgically excise the whole abscess capsule, if possible, and then make sure the cavity is kept open and clean, possibly using Manuka medical grade honey (25+) to pack the wound. Injectable penicillin or some other antibiotic, given regularly over a period of weeks/months.
Some vets will want to remove affected molars at this stage, but it may not be necessary given where your rabbit's abscess is?
2. As above, packing the wound and with the injectable antibiotic, but lancing and draining the abscess cavity instead of a deep operation, which is quite traumatic for the rabbit. As you know, getting them eating again afterwards is of prime importance.
Good luck. I hope you can get your vet on board with aggressive treatment as soon as possible.X