You say that as if the official name of the church is a secret -- it's not; it's common knowledge.
And the church has always been staffed by the Redemptorists, not diocesan priests. My guess is the Order owns the church, and the Redemptorists in recent years, I hear, are little better than the Jesuits (or at least not as noisy). The Orders don't answer to the bishop.
My purpose in mentioning that was all the reports I had read on funeral arrangements mentioned the “Mission Church.” Then Mrs. Don-o’s post said it would be in the “Our Lady of Perpetual Help Basilica.” Not being from Boston (at least not for fifty years as a child!) I assumed it was two different churches and the funeral had been “bumped up” from the Mission Church (which I thought of as some lesser, Congregational type church) to a more formal Roman Catholic church with the acquiescence of the Archdiocese. I was surprised and somewhat relieved to find from a news report (http://news.yahoo.com/s/ap/20090826/ap_on_go_co/us_kennedy_burial) that they were one and the same.