i don't think there's any harm asking them.. why not give it a shot? after all, FFF is a sanctuary. i think you just have to provide the funds for the dog's care. if you can't keep this pooch permanently, FFF may be your best bet. it can pretty hard to find adopters for mongrels, let alone tripod ones.. i'm afraid that's a sad fact of life.
i've been fostering a tripod dog for almost 3 months and no one has adopted her.. not even after uploading her profile here, putting up posters in veterinary clinics and a church, and not even after an article was written about her in the star newspaper!!
you may be your tripod dogs only hope!! good luck!!!