This is inaccurate in several respects.
First of all, the Benedictines are not as a group called "Olivetans." The Olivetans were a branch of Benedictine reformers, striving for a more austere and ascetical monastic practice. Even at their peak centuries ago, they never more than a small minority within the Benedictine Order, and now they are much dwindled in number.
So that's a very slender connection to Olives.
Also, Benedict XVI is not, and never was, a member of the Benedictine Order. So the slender connection turns out to be no connection at all.
Secondly, Cardinal Ratzinger never endorsed the reported Medjugorge mystical phenomena, and says that supportive statements published hither and yon were "made up out of thin air."
You can read about that here:
www.unitypublishing.com/newswire/finaldec.html
Hi Mrs. D!
How's the schooling going?
We are getting serious about our "Latin is Not so Tough" lessons here!
But is he associated with that "Secret Opus Dei" society?
Pope Benedict XVI is known for going on retreats to Benedictine monastaries (so saith the Vatican watchers yesterday). Is that the connection? Maybe, maybe not. Everyone got hung up on the Benedictine angle, to the exclusion of all else. The more common usage of the olive is 'peace', asin, olive branch. The whole problem is that just about anything can be twisted to meet prophecy. And that assumes the prophecy isn't a fraud to begin with.