Shane, I'm not familiar with the song. Who does it? or more to the point, who does the version that you like? As a beginner/intermediate, training my ears to pick out the key is one of the things I do when I listen. Not great at it but getting better. It helps me to sing along with the music, because I know what keys are best for me. If I do a 2d at the turnaround on the two or three keys I have it narrowed down to, one of them usually stands out as the right one.
Somebody may have it. Good luck, Michael