I'm good with Rapid Spell and using a Silent metamagic rod. The adventure I'm going to be running isn't very good at telling you how the cleric manages to finish the unhallow spell during a funeral when he hasn't been there for 24 hours, but rather maybe 20 minutes. As well, he's not supposed to be heard by anyone because it's silenced, and he's an 11th level cleric. The feats are given, but he's missing one for the HD he's got, and he's not carrying a rod. You're just supposed to accept that he doesn't have the feats, but was able to do everything two spell levels higher for free, and in less than the 24 hours, surrounded by dozens of people.