Wow, that is some intricate search there I will listen to them as soon as I can. To make it clear: it ressembles some parts of the harmonica part during Running To Stand Still, on Anaheim 11-14 and Mexico 11-25, right?
PS. How have you contacted u2gigs? Thru their feedback form on the website, or through any social network?
According to Pim: "At the end of Running the audience sings along "Still Running" so well that when the song ends Bono motions to Larry to go on and improvises a whole extra verse that to this day remains unidentified"