I doubt that any groom would want to be hardwired to a camcorder during his wedding cerimony. Don't most of them walk out of the church, hall or event center with their new bride ahead of everyone else usually? dragging a hardwired cable is asking for trouble and is way intrusive and limits mobility. I know he asked for any solution, but that would have to be at the very bottom of the list of things that you could do to get the sound of the cerimony. If that was the route you had to go it might be better to hardwire the priest. A small recorder in the pocket or rigged to the small of his back is a decent idea, but so is using a wireless system. Tx on the groom or also on the priest/preacher/MC and the Rx on the recorder or camcorder.
Sennhieser makes some very nice, small and very reliable units. Either get one of their new G3 systems or look for an older G2 system. Both are excellent at transmitting high quality sound wirelessly back to your location.
The other thing about putting a small recorder in the grooms pocket is that they are usually pretty nervous and figity. Grooms do all sorts of odd things before getting married. I know I did! You would hate, hate, hate having him accidentily turn off the recorder (H1) in his pocket right before the cerimony starts and you get nothing. With a wireless system, you control the recorder. And both the G2 and the G3 come with belt clips built in as well as all the cables and a mic you'll need to make the system work. Amazon and B&H sells the Sennhieser systems as well as Trew Audio.