This is a perennial problem of TV talent shows - the tendency for people to get carried away with the song, rather than the singer and the performance.
It's the rock equivalent of Nessun Dorma - a song so powerful that my mum could get up and give it a bash and people who be signing along and smiling.
So - if you separate the sheer awesomeness of the song, and look at the performance, it's adequate. The guy has a good voice, and presented well, but - the age-old question - would you get a babysitter, get dressed, travel into town, and pay a tenner to watch him perform a whole gig?
Based on this - I doubt if many would - and that should be the measure of a talent show audition - not a knee-jerk reaction to a rock classic.