I think the problem is with you. You seem to be a very strange person for not have shown any interest in that "uncle" by asking him questions. It is not the word "uncle" that stopped you from getting into a conversation with the "uncle". It is your attitude.
Besides you said, he had a kid of your age and you still were not able to fully communicate with her. So uncle or no uncle, the problem is you.
I can imagine you being in the room, hands on your lap and not uttering a single word unless questioned. You will pass as a "kasto gyani" choro/chori in Nepal, but in western country, you will pass an a weirdo.