I've been to a couple of weddings, mostly listen to public radio. I've seen Deadpool, so I have probably heard "Low", but it didn't make an impression --- I just found it on YouTube, and it doesn't ring any bells. Sorry. I know lots of movies (and I do watch lots of movies) include music, but unless the songs are already familiar or you take notes during the credits, associating even a memorable song with the artist(s) that produced it is not a given.