It looked that way to me

No I think there was an echo or similar on the mike which continued after he stopped.

It sounded as if the note carried on after he finished singing The end of the song was appalling, couldnt understand what he was singing

Nope but there was a tiny section where the bv's took over to give him time to get ready for it. Perfectly allowable and no worse than Mariah Carey getting her backing singer to sing difficult notes.

It was all very strange.