Yup. If she asks for Sanzou's arm then the suggestion is it wasn't entirely fortuitous that the youkai cut off Koumyou's. Next question being, what do we need a physical bit of these Sanzous for? ...especially since they didn't use any of the scorpion-youkai-killed-Sanzou's flesh (that we know of.) OTOH she may have forgotten there was a scorpion-youkai-killed-Sanzou in the first place. Mangaka do that, alas.