I can't help but feel like the author sounds excessively credulous. I had to stop reading after he wrote "I could tell something big was up and there simply wasn’t time to debate the merits of handing over my source code to the NSA", because at that point my eyes rolled so hard they fell right out the back of my head. After I put them back in, I skipped down to the comments. I have a hard time not agreeing vehemently…
Even all these years later, he doesn't even consider the possibility that he was manipulated. He betrayed all of his users at the drop of a hat, and all it cost the NSA was a single phone call. Crazy stuff.
This is why he was asking about their ability to break 256 or 40 bit encryption.
So there was no trust broken in sharing the source code.