That one mistake at the end of the concert when there is a big "sorry" above Clapton's head is NOT there because of a wrong note Clapton played.
Me thinks it was the keyboards that messed up a bit. At around 55 minutes you see a closeup of Clapton's fingers doing their mojo. And then, the viewpoint switches suddenly to a camera on Claptons left so you see him with the keyboards behind him. It is at that time during an otherwise perfect performance that the pitch goes through the ceiling and you see Clapton almost turn green (not really, he laughs it off). The director chose to let you see the guilty party.
During that weird second you can still hear Claptons guitar grinding away, undisturbed in the groove.
Eastern tapestry alway has one flaw in it because only divinity can be perfect. This too applies to the concert which is a masterpiece ever so slightly.