I don’t know if it’s true, but I’ve seen several pics of what was supposedly in those envelopes over the years.
The pic I saw was a card-like thing, not folded like a card, and it was a formally printed one with Bush Sr. pic on it. Underneath the pic it had his name printed, and then just above the name, there was a handwritten line that said, “They have everything. Sorry.”
That’s from memory - don’t guarantee the accuracy, but that was the gist of it.
Thanks for the post with the info! Somehow I don’t think we will ever know the full story.