After all of this time, I think if someone was going to crack they would have already done so. JMO
Of course, if LE hasn't questioned this "follower" yet, maybe he still feels safe. Perhaps he won't crack until LE closes in on him and his "leader."
See that's what I'm thinking., that if LE questions this person, it might not take much to make him/her talk. But until then, he/she might think they're safe and LE doesn't suspect anything.