The German keeper, who paid for his own flight over to England to train with the Eagles and land first-team football, has left the club after Francis decided not to offer him a contract.
Francis took Scheur on trial when he was left short in the goalkeeping position after Alex Kolinko joined Matt Clarke on the injured list.
He has Nik Michopoulos on loan from Burnley and Kolinko is close to full fitness so Francis has decided against signing Scheur.