Bobert, I am going to be facing that same problem.

I've been working with a 53-year-old man who has never played anything but wants to learn to play the guitar so he "can sing to the Lord'.

He is making strides on the playing, but so far, I have not been able, far from getting him to make so much as a peep, getting even an acknowledgement that he knows a song, any song. I have NOT made an issue of it, of course or even remarked on it. But I have thrown out the occasional well known name of a singer and he has never picked up on it.

Except for one time: in demonstrating something I sang a bit of one of my songs for him, and he marveled, "That's as good as Dolly Parton!" hahahhaha I despair for him. :)