Narayana Who?

This morning I was giving the Bhagavatam lecture; we are discussing the story of Ajamila and the verse mentioned that he chanted the name of Narayana.

One initiated devotee in the audience asked: What does it mean Narayana?

I attempted--probably successfully--to hide my surprise and I explained that Narayana is a name of Krishna, meaning the shelter of all living entities.

What to make of it? Is it a freak event, a twist of fate that this person never heard the name Narayana before (or after) initiation?

Should we take it as a positive sign that in ISKCON we are so focus on the krsnas tu bhagavan svayam consciousness that other forms and names of God are hardly known or recognized?

Or should we take it as a serious alarm bell about the lack of formation (some of) our devotees have?

Later I asked the person if she had read the Bhagavad-gita, and she confirmed that she did, in full. I checked the Folio and found that the name Narayana appears about 20 times in the book, and so I keep wondering...