Reminds me of one of the ESPN Football commentators (Scottish) who had naturalised and was going to Liverpool to cover a game, last minute he realise his US Passport had expired so he travelled on his British one.
Much studio discussion about how he was going to come back.
So he turns up at the Airport presumably Manchester and they would not board him, no US Passport and no ESTA for his British Passport.
He applied for ESTA and was approved, so flys out on the next flight and gets to US and explains that yes he is a US Citizen etc etc and they let him in without issue.
I thought it was interesting as it showed how little the ESTA system knows.
IF the guy at the PoE recognised him I do not know.