Acapella Concerts During Sefirat Haomer: A Curious Psak Halachah

Perusing the pre-Shabbat edition of Mekor Rishon last Friday, I noticed an interesting piece at the bottom of the front page of the paper, announcing an upcoming concert of the Maccabeats, which took place this week.

The headline: "The Jewish Group that Obama Likes Arrives in Israel With a Special Vocal Show for the Days of Sefirat Ha'omer"

OK - the Maccabeats are coming. I'm not entirely sure why Israelis would care (or even think) that U.S. President Obama likes the Maccabeats (from the YouTube video it's pretty clear that he wasn't in the room when they performed, but whatever...)
Yet, a quite curious quote appeared towards the end of the piece.

To the question of how a religious musical group can perform during Sefirat Ha'omer [Maccabeats Manager Chaim (Julian)] Horowitz answered, 'We received permission from Rav Hershel Schachter (Rosh Yeshiva of Yeshiva University) who said that shows with positive content are better than shows that are not appropriate for this time of year. He said that from our shows there's a spiritual elevation.'

Really? Not only did Rav Schachter (recently announced winner of the Katz Prize for applying halachah to modern life) permit the Maccabeats to perform in Israel during the Sefirah - he also endorsed the group! Moreover, Mekor Rishon's sister paper - Ma'ariv - has publicized the Heter under the title: איך מופיעים בספירת העומר, אם אסור להשמיע מוזיקה? - "How Can They Perform During Sefirah if it's Forbidden to Listen to Music?" There Rav Schachter's heter receives prominent placement - basically the same article, but with an entirely different emphasis on the halachic leniency.

I found the psak troubling for a number of reasons.
From a logical perspective, who says that people have to go to any performance during sefirah? Why is the choice between going to the Maccabeats and going to hear Madonna? What if it was between going to hear the Maccabeats and not going? Secondly, why would Rav Schachter issue a psak allowing the Maccabeats to perform in Israel? Shouldn't he tell them to ask someone in Israel? Rabbis in Israel would indeed be correct - and I know that some did in fact raise an eyebrow at this article - to wonder why Rav Schachter would issue such a psak.

It turns out that the psak really is questionable for a very simple reason: Rav Schachter never gave it.
When I reached out to Rav Schachter's son with my questions, he answered me as follows (shared with permission):

I spoke with my father about your email...He said he does not recall any sort of shailah or conversation with the Maccabeats at all. He agreed with your concerns, and felt that if in fact the crowd they are trying to attract, are the types that would otherwise doing things that were less in the spirit of sefira, then they should certainly be encouraged to go here. But this is not something he would suggest, for people who otherwise would not be involved in sefira appropriate activity. 

Moreover, my father said he has always been careful not to issue psakim for Eretz Yisrael, the same way that he doesn't like when Eretz Yisrael rabbanim issue psakim that are relevant to America. He said that makes this conversation with the Maccabeats even more hard to believe, as he in the past has almost never issued rulings that impact the society in Eretz Yisrael.

So, it turns out that Rav Schachter did not in fact permit the Maccabeats to perform in Israel.
Incidentally, the show sold out - entirely through advertising on Facebook. I wonder how many of the Maccabeats' fans hesitated due to halachic concerns but ultimately attended having heard that Rav Schachter allowed it.
This also raises a more disconcerting question: If Rav Schachter never issued the psak, why did the Maccabeats' manager say that he had?