[Rippersnapper]

I thought the chaperones were asked by the FBI not to talk.

If I recall, that was proven to not be the case. Seems they talked to one chaperone and they cleared that up.

[CitizenM]

Right. That chaperone stated the FBI had not asked them not to talk. I think, however, between Nat's family and the chaperones there was an agreement that the chaperones would not talk. In order not to hamper Nat's mom's efforts down there. IIRC