No one can rell you what to do in this case...all I know is that I truly believe in living the "Golden Rule". If I, in good conscience, couldn't tell them what they should be told, then I would have to either find another job or pass the calls about that subject onto someone else. You know, the people that had you sign that paper are NOT the ones that will lose sleep at night over this. For me, if I heard someone in pain, I couldn't keep my mouth shut...I just couldn't. What if they were calling as a last resort and you have to tell them "Sorry...too bad..." I'd at the very least recommend they call a crisis center. What if they became suicidal??? Anyway, this is apparently bothering you pretty bad and all that's going to do is make your own anxiety issues worse and that job just isn't worth it. I really do feel for you in this situation...HONEST!
"The measure of a man's real character is what he would do if he knew he would never be found out." Thomas B. Macaulay