Explanation:
I haven't read the book so I'm just basing my answer off common sense and my preexisting knowledge of history so please take this with a grain of salt.
I believe the connection would be more of a metaphorical one as Harriet Tubman is an American abolitionist. Flying/wings would represent Harriet's goal of trying to abolished slavery and make slaves free. The song, "Go Down Moses," is a song expressing the freedom of slaves, relative to the suffering of the Israel's when Pharoah was oppressing them which can be found in the Bible.
I hope this helped a little bit!