IMNSHO, they didn't answer the direct question initially because they either did not remember, or did not realise it was significant.
Either that continued for the whole scene, or the realised based on your having all the NPCs asking about it that you wanted them to answer it...so they didn't, because they don't trust you and thought you would use it against them somehow.
Which three people?
More to the point, I am not arguing in good or bad faith, because I am not arguing at all. I am trying to help you.