Switching from Levaquin to Cipro isn’t likely to help anything, since they are very similar drugs. The numbness may change very, very slowly, even if the metronidazole caused it.
I haven’t had any issues with C. diff or fungus. I do take a very high dose of VSL #3 (4 DS packets per day) - that’s a bacterial probiotic that might help with fungus overgrowth. Unfortunately it’s expensive. The usual probiotic to prevent C. Diff is a yeast formulation (S. boulardi), sold as Florastor, but I haven’t used it much.