tl;dr it depends a bit on What Exactly You're Doing, but generally if you want bones to compost in a reasonable timeframe you want to boil them up or burn them or grind them or at least chop them up a bit first, which... I do not get the impression that Recompose is intending to put corpses through a mulcher, and certainly that's not how it worked in the book! I would be fascinated to know more details about how exactly they are achieving this, because on the face of it I'm very much at ???!