I hadn't know that she'd done this, but it's done beautifully, of course. Didn't know anything about her involvement, however limited, but a fun find for me, nonetheless...I love me a good Liz Callaway scoop!
I would think not. I've not found anything stating that she was - Schwartz likely just brought her in to sing the song, not play the role. Interesting to hear the changes/choices, but even more interesting that not much about that song has changed from then to opening night to even now!
It's really fun and interesting to hear the notes sung as they were originally put to the page, and compare with how the artists' contributions shaped it into what we are familiar with, now.