I find it hard to believe either the FAA or AC hindered the investigation at the outset. It was in middle of the night, if the crew didn't report it and the lone ATCO, busy with duties, didn't report it until shift change, the plane was probably being readied for departure before there was any hint of an incident. In the morning, the AC flight leaves for YYZ or YUL, bingo, no CVR recording. If anything is suspect, it is the crew's failure to report and trip the CVR circuit breaker. I'll admit it is possible they missed it all on the first approach, but I doubt a sentient crew didn't pick up their mistake on the second approach. Light bulbs had to be going off.
Then, the question is about AC's safety culture. Does it inhibit honest reporting of mistakes. Did the crew feel likely to be disciplined? Were they cognizant of the error and, if so, thought it could be hidden. Their simple answers implies a " cover up" on their part that can't be uncovered now.
GFK