That's probably it, Ellie,
and you might find the key in his lyrics, that they have an even deeper, more significant meaning than you've been enjoying. Why else would the dream need to bring it to your attention.
It's also possible that there is a more personal meaning meant for just you. You may have 'called him down', by thinking of him intensely and lovingly when you were listening to his songs. In other words his spirit may have been drawn to you. If so, the key he gave you could be a remembrance so that you can meet later in the afterlife.
I once got a less personal personal invitation to a concert in the Afterlife from a professional musician I just happened to sit next to on a plane for several hours. He was temporarily out of the physical due to celebrating/relaxing with maryjane. He reeked of it so heavily that I was having grumpy thoughts about maybe shoving him out the window just to get some fresh air. (
I didn't mean it.)
I was surprised when my grumpy threats were interrupted mentally by a voice that apologized and asked me to be sure and come to his big songfest in 'heaven' that he was planning for when he went over. How will I find it, I wondered. His thoughts responded that everyone was coming so just come along with them.
Only when the stewardesses came to rouse him for our landing did I hear his name and realize who he was --then it made more sense.
Bets