Supervisor doesn't seem to be particularly clued up, but are you sure that no need for photo ID for Jersey - just because they normally don't check doesn't mean it's not a requirement (https://www.gov.je/Travel/Informatio...aPassport.aspx)

Certainly for UK-Ireland CTA you can be asked at UK end (albeit very rarely) - have had UKBF set up a document check for arrivals at LCY, and have had passport checks at T1 at the end of the Green Mile in the past.