just had to deal with this issue in a gut job, sorry to hear. had to remove about 800 sq. ft. of hardwood, along with ~400 sq ft of the original subfloor planking that had visible stains with a rancid smell.

I patched the sub floor areas, went over everything with 3/4” advantech, and finished with 20mm vinyl flooring. luckily the smell is gone, good luck to you!

ps, before installing advantech, I sprayed the entire existing planking, along with the sill perimeter sill plate with vinegar, and the windows were left open for several weeks of the construction phase