If Five Finger Death Punch really is not a satanic band then why do they say I believe in something seen?

There is no evidence to suggest that Five Finger Death Punch is a satanic band. The lyrics to the song "I Believe in Something Seen" do not contain any references to Satan or satanism. The line "I believe in something seen" is likely interpreted as a spiritual experience or religious truth, and not as a satanic affirmation.