Hi , there and welcome to NeuroTalk.

Recovering from metronidazole can take
Some time. But some studies do say recovery
Is possible.

I'd raise the benfotiamine to 300mg for a
Couple of months, as this helps with the
aldehyde excess metronidazole can cause.

Also the damage this drug causes tends to be
to the myelin of the axons. Some studies show
white spots to the myelin in the brain, for example.

So using nutrients that facilitate myelin repair
may be useful.
omega-3 in fish or Krill oil
Methyl cobalamin B 12
Methyl folate as Metafolin 800mcg daily
A good magnesium supplement (not oxide type)
some activated B6 called P5P

All help with this. You can find more suggestions
By Googling "supplements for remyelination"

I think acetyl carnitine may help too because
It is used successfully in other drug induced
Nerve damage issues. (Eg:chemo and antiretroviral treatments)
Start at 500mg a day and you can increase to 2 grams
A day in divided doses .