I think the real problem is that Carrie Underwood does not sing Gospel\Christian music solely. She has decided to pursue a career in singing Country Music. Your Church leadership only sees that aforementioned fact, thus concluding it is Satan's music.
I happen to believe that is a flawed and ridiculous way to look at this song. The song is very inspirational, in fact the whole CD is. The song covers all of the most important aspects taught in Christianity. You have a person who is driving home, apparently heart broken about something. This person has a lot on her mind, and lets her mind slip away enough to be driving to fast in an ice storm. This person looses control of the car (also a metaphor for the obvious loss of control of her life) and spins out. After having not had a wreck, and realizing she and her baby are OK, she feels an overwhelming since of gratitude to God, as well as having been shook out of her self pity enough to realize they need help. Realizing she has been traveling the wrong way both spiritually and physically, she calls out to the Savior, Jesus, our only source for real hope and salvation. I fail to see what is so bad about this song, and what supposedly makes it wrong to be sung in your Church.
When your Church leadership says they think the song is a metaphor, I think they are trying to say that neither the song writer nor the original performer meant for this song to really mean for Jesus to take the wheel of their life. I think, based solely on what you have said here, they are approaching this song more like it is a feel good song and not a real Christian song with solid spiritual significance. I do not agree with this train of thought, but I believe this is where they are coming from. There are many songs in hymnals that are metaphors for Jesus. Jesus is not a potter. No where in the bible will you find Jesus being refered to as potter. Yet the phrase "thou art the potter, I am the clay" is written in to a hymn and is often used by Christians in other areas of their faith walk.
If I were in your shoes, I would be praying to the Lord about seeking another Church. The reason is very simple. If your leadership says no to a song, or anything else in which they can not give a sound biblical reason for their saying no, then you have flawed leadership. How can they say they know God is leading them to go in a direction, if they do not know why they said no to something else. People like that have no direction themsleves. How can you and I count on them to lead us?