I'm not sure that's the reason you're being downvoted. You could be being downvoted because the BBC article in the OP says that there was a New Yorker article and The FAA have said there is an investigation. You're concluding that the FAA is doing the investigation because of the New Yorker article. Another (perhaps simpler) explanation of the same facts is that the FAA were doing an investigation (either because of what the agents on the ground told them or because of the flight data or whatever) but it wasn't reported in the press (and the FAA didn't make a statement) until the New Yorker article came out.

Also you're probably further being downvoted because whining about being downvoted is a surefire way to get downvoted.

Nah, it's a surefire way to get upvoted - I get 2 back every time people overreach and go nuclear

Good they were in the room at the time. I would absolutely want a public accounting for the gap between what the regulators in the room saw vs. why the grounding after the article. Abundance of caution over a nothing-burger? Ok, just say so. A bad call made by the regulators in the room? Ok, human error exists. An intentional effort to keep the regulators need-to-know or an intentional looking the other way? Big problem.

No, the investigation was started almost immediately after the flight.

It's simply being reported in detail now.

Yeah, it definitely smells more like ass-covering for optics than anything they were concerned about at the time of launch.