If you do an internet search for Medjugorje you will find *all* kinds of things. One of the things you will *not* find is any kind of Vatican endorsement or approval of the apparitions there. In fact, you'll probably find as much "against" it, including some of the local episcopate, as you will find things "for" it.
Peter is absolutely correct in saying that an investigation is not an endorsement--it's not even close to being so.
My own "close encounter" with things Medjugorje-ish was a friend in the U.K. who, upon a visit there, was deeply converted to Catholicism from Taoism. Was it a "real" conversion? Certainly appeared so to me. Was it a result of the "apparitions" there or of something else? I don't know. What I *do* know is that once he was Taoist, and then he was a very reverent, pious, and sincere Catholic. Go figure.