GAON: “Speaking about the Mishkenos Yaakov, I recall his understating on Mefulash (as per Rashi, he quotes a Yerushalmi i think that argues) is not like RM nor R”A .”
I agree the MY’s understanding of mefulash according to Rashi is not in accordance with Rav Moshe nor Rav Aharon. However, the MY ultimately is not clear regarding the criterion of mefulash umechavanim.