What Happened to Saladin 6. The Lion and the Demon?

So I'm playing through the Saladin campaign on DE and I just finished 5. Jihad! Mission 6, the final mission where you siege Acre, should have popped up on the campaign map, but it didn't. The first five missions have a checkmark and the Saladin campaign on the African Campaigns menu has a checkmark indicating that I've completed it, but again, I haven't done mission 6 and I can't access it.