I am actually going through the process of seeing if our homeowners insurance will cover mold remediation. It does seem that getting fresh air lessen stress my light and noise sensitivity a lot. Still I consider that this could be downstream to cci as I didn’t always have this problem despite being in the same house for years , and it seems that cci could cause mcas issues. Yes benzos really help w hyperacusis but I am tentative about taking them too often and losing the effect
Given that sensory overload is common in ME patients I suspect that your husband's ME was hypersensitive to the mold toxins. This isn't to say the mold caused the ME however.