We buy two ply rv toilet paper at Walmart.
Since 2006 I have had an rv ( PC and Roadtrek) with a macerator pump and I have never, ever had a problem with the pump getting stopped up. Never. I don't worry about toilet paper but we are mindful of hair going down the shower drain because that will lock a pump faster than degradable paper ever would or could. We have a small screen designed to fit over the drain in the shower specifically designed to catch hair. They cost three or four bucks and you can buy them at most places like HD or Lowes.
Personally, I have always meticulously maintained our various motorhomes for thirty five years of enjoying them but we bought them to use and we use them. Everything on them. We have used campground showers once in all of our years of rving. That is why we have a motorhome - to have our own shower, food, toilet and bed.
Paul