My Bunny is Anemic, any ideas?

Hello! I'm new to this group. I have two bunnies that we've had about 3 years, adopted from a rescue group. Holly stopped eating about 5 weeks ago. Took her to the vet and we started her on penicillin, pain meds, fluids of course and Panacur, because she was leaning to the side. She started getting better, started eating quite well for about a week, then the week after, stopped eating again. Two weeks ago, she ended up having dental surgery and she had some pretty significant molar spurs, etc., one growing into her cheek, etc. They told me they've never had a bunny start eating so quickly after coming out of anesthesia! She ate that night, but by the next evening, we were back to not eating again. The vet wanted her on cisapride three times a day until she was eating and pooping normally, but nothing really happened in that direction.

Over Thanksgiving, I slowed down on the cisapride and stopped the Panacur. She had a few times there where she would start eating again, greens, and then not eat at all.

Through all this, she has lost about a pound and a half, she's pretty bony now. Took her in this week again for xray and blood panel. Xray only showed one kidney, some gas pockets. Fecal test negative for parasites. Bloodwork shows she's considerably anemic, low serum protein levels, couple of her liver enzymes are mildly elevated and her white blood count is below normal. The vet said no obvious signs of cancer, and her kidney function looks good.

I'm wondering if anyone in this group has any ideas or thoughts for me. We stopped the antibiotics (we had also started Baytril for a few days and she seemed worse) and started her on a probiotic that has a paste and a powder that you put in the water, with vitamins and electrolytes. She seems to have perked up since then, but only eats a few bits of greens here and there. Syringe feeding her with American Pet Diner's Critter Be Better. She had runny poop for quite a while, and it was very smelly, which is improving now.

Thank you,
Tracy