Hey there beyondET, I did a quick study of Frost Like Ashes, not quite sure what to make out of them, they're a Christian band, then a read the lyrics to their song Lord of Darkness. The song seems to piant a picture of God the lord and giver of darkness and that He can fulfill ones disire for darkness, maybe I don't get what metal is about.
Anyhow, if something is evil then it's evil, you can take the lyrics of a song and put them into a godly context, but the song itself is still evil and can't be supported for what it really is.
Like when John Lennon sings" I really want to see you lord" he's singing about Krishna, every time that song is played Krishna is worshiped.
Now you say evil wins when we separate from what we are convinced is evil, but would it not be much more effective for Satan to convince us that what is evil is accutaly good? Because then we would be embracing evil, we would be deceaved. It's better to sacrifice something that will just fade away anyhow for the sake of righteousness.