Makes no sense. If they were members of a terrorist group, and didn't reveal that information, they weren't in the country legally, but under false pretenses. If I find out the guy next door is a mass murderer from Lower Slobovia, I'm not going to keep the information to myself just because he's in the country on a "valid" visa.
IF you're an incompetent working for the CIA, that, apparently is exactly what you 'd do.
The ultimate refuge of the incompetent: it's the law.
Which brings us back to the question obvious to anyone with an IQ greater than 12: What kind of a law was that? who pushed it?
Why?
"Good intentions" will not excuse this enormous national security blunder. I suspect that Jabba "the Swimmer" the Hutt had a hand in all this also...