Cows:
It would be a very brave regulator that ignored the recommendations of the independent safety auditor. In the UK the CAA make great efforts in absolving themselves of any risk ownership and I can't imagine the FAA being any different.
In the US the NTSB makes recommendations. As an independent agency with its own body of expertise, the FAA sometimes does not follow them.
I'm sure someone will explain it better but I think the NTSB is decreed to be independent of improper outside influences and
afaik does a good job of that. OTOH it seems to me that the FAA charter is not so saintly - its job is to keep airplanes flying safely, and not unlike other government agencies that touch on commercial interests it seems to have become more and more aligned with those interests over the decades.
This is the same body that, for instance, finds it difficult to mandate that our regional carriers hire well-trained pilots and pay them enough to assure they can afford a place to sleep at night and don't need a second job to raise their pay all the way up to our poverty level. I'll bet they're not having fun with this high-pressure situation - between a rock and a hard spot for them.