A 53' motor yacht probably could support Incinolet without any problem. And there's a reason the Alaskan fishing
fleets love them, their reputation is flawless. Of course, guests may have qualms about doing their business on a crematorium. You know, you're really sure this won't go off now?(G)
With any type of home/land toilet except those wonderful urban flushometers, you're going to have a "tank" of water stored in it all the time. And unless you make that into a custom SEALED and vented tank...and a way to dry the bowl when not in use...slosh slosh, the Persian carpets are going to get wet.
There are some marvelous one-piece stainless toilets used by Airbus, and some one-piece carbon fiber toilets made for the high end marine market in Italy
. I'd suggest some deeper digging to find a better toilet that was intended for marine use in the first place, rather than dealing with sloshing water all the time.