We are in the same boat where structure very close burned at the edge of the burn scar. I would really like to replace my everything but insurance only covers remediation. After the remediation team came and cleaned all the ducts no smoke smell remained. I think you might just have to accept what you can achieve. Also, just refrigerant is exchanged between the compressor and inside your house. So only the ducts and filters matter.
Just curious why you’re just now getting your house remediated? You didn’t do that a year ago?