[Hblick48]

That recall is for the Dometic 300 which is all plastic. OP noted that he has porcelain which means 310 or 320.

I have a 310 and was also had a leaky seal, thus would lose water. First, I got some of the grease specified by Dometic at a big box store. Wasn't 100% but better. Now, before I put it into storage between trips, I add some extra water to the bowl, and then pour in a little liquid RV holding tank valve lubricant. It sinks to the bottom of the bowl, and keeps the seal soft and pliable. Haven't had a problem since starting this routine.