He will join Katie and Malachi in the live showdown on Sunday night.
It's delayed from its usual Friday slot to make way for Children in Need.
Headteacher Richard Park told David and Nigel it was between the two of them.
He said both the lads had impressed them but that they weren't convinced Nigel had a long-term future with them.
Wannabes chased!
Meanwhile, the music wannabes busked for visitors to the Brent Cross shopping mall in north-west London in aid of Children In Need.
They made an impressive £892.42 and were chased by fans!
And Sinead's been chosen to sing live on Children In Need this Friday, after winning the vote of Radio 1 listeners.
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