I think you've got a problem.
If I were you, I'd want to test different cameras in the conditions I'm going to be shooting in before making a purchase.
Have you talked with other people in the business in your area? I'd want to find out exactly what they're doing and how.
I'm not sure if there IS a camera that will do what you want. You may have to make some compromises. Perhaps you could hide some 250's here and there.
Have you considered shooting stills and using your video editing software to blend them in to your wedding video. If you shoot scenes of preparations, outside of the church (daytime) and the reception, you could use panning & zoom to sort of animate the stills and make a nice slideshow with the actual live audio and sandwich them between the prep video & reception video. At least this way your color rendition and quality would be good.
By the way, I'd invest in a wireless mic system like Azden's and use a lavilier mic on the groom instead of a shotgun. Use another mic to plug into the house sound system or however you're going to pickup the music, etc. and blend them as needed in your editing software.
Speaking of using a shotgun on the groom, kind of reminds me of my own wedding...
Good luck (buena suerte), & let us know how it turns out.