Boundary of Muzdalifah and Mina

The Saudi authorities have included a considerable area of Muzdalifah into Mina proper and named it as New Mina and they accommodate pilgrims in this area as if it is Mina proper. However many haajis returning from Arafat in Haj also spend the night here as for all practical reasons it is actually a part of Muzdalifah as per the boundaries that existed during Prophet's time. So does Wuquuf of Muzdalifah of these Hajees get fulfilled? And also then what is the status of haajis who are lodged here (New Mina) instead of within the actual boundaries of Mina as it existed during the Prophet (Sallallahu Alayhi Wasallam's) era.