Generally, I would agree with you. I threaten to kill you if you expose it and you name names, you might be safe. However, if I mention your pretty bride and little girl and your dog by name, you may not be as forthcoming. Especially if you believe that those threatening you have the means to make it happen and look unrelated and coincidental.
If you come out publicly with the tape and said you and your family are being threatened nothing much can happen. If it did there'd be investigations up the yeng-yang digging under every dark corner of the government. The last thing the FBI or CIA want...
Once it is out, there is nothing further gained by going after him.
Also, absolutely nothing prevents him from making copies and dropping them off at various news organizations anonymously.
BTW, I think I saw the video as well if its the one with streaks of light rising in the distance.