I hope he gets better but,
Mind explaining why the vaccine would help for this? Is there any even anectodal evidence of the vaccine helping for "long haul" symptoms?
There is anecdotal evidence in the vaccine helping for those who still have Covid issues due to covid-19 still hanging around, and the vaccine provides the immune boost needed to get rid of it.
Not enough data to prove that, and would only make sense to help for those issues caused by Covid-19 hanging around, and not damage caused to the body by Covid.