If you are worried about being labelled an apostate then just talking about the UN will be a huge mistake.
If the elders coming to see you do any kind of research on line, they will see that the UN issue is a favourite among apostates. You are therefore already at great risk of being accused of being one.
If you flash a UN letter under their noses, you will be hauled before a judicial committee quicker than you can say 'repentance'.
The fact they know you have been talking to either your wife or her mother has probably already put you in the position of actually being an apostate.
If you don't want to get booted out, it would be advisable for you to downplay what you know and keep all the information about the UN to yourself.
Best of luck on that one...