Divine the Tainted

For my paladin, when I discuss prereqs it shows I can take Divine the Tainted with prereqs of *SNIP* I thought it was just far more expensive than I remembered, but when I look at my own logs for previous paladins, the edge showed up as an option near things like strong back as far as cost. MY current list of options is far above that on the list, just with the edge in question missing. Wondering if there is something wrong with that edge, or if there is a different requirement that I am missing like not orderly this time when my other example was a neutral ethos. I have long since gotten past any level requirements that could have been in play.