that's not true, while some have sensory issues that cause them to easily be overstimulated, others don't have these issues, or have the opposite, and look for stimulation. But this shouldn't influence your social response to anyone, because most people on the spectrum do indeed enjoy being social regardless of the sensory issues.

About the being non verbal, most people who are on the spectrum are able to speak and say many words, even if someone says they are "non verbal". Most parents use it to say that there child doesn't speak, as in not being able to have a conversation. While the exact meaning is individual to the person, most don't use it to mean that the person has never verbally said a word before. I can say with a certain amount of certainty that he does at least say words, even if this is the first time you ever heard him. Just saying, a lot of people understand "non verbal" to mean "mute", having never talked, when most of the time it is not the case.

Being autistic and non verbal also doesn't affect intelligence, so he might actually be thinking your being silly asking him if he can say his name and these similar type of questions
Many who are non verbal totally understand what others are saying, but might not be able to respond verbally.

I am not always able to speak using my voice, and I am almost always never able to speak to people I don't know. I totally understand what people are saying to me, just not able to get my brain to get my thoughts out in speech. When I cant speak, and I need to say something, I use alternative forms of communication, like my communication device (fancy laptop that talks), or sign language, or various other forms of communicating.

If he is non verbal, he might use some other form of communication that your not aware of, or that you might not be able to understand

You might be surprised at how intelligent he is if you find the best way to communicate with him