Hi Scoobysue

Sounds like you had a dreadful day.

Unfortunately I'm not sure that either a travel insurance policy or cradit card insurance would be able to compensate you in the circumstances. Travel insurance will generally only cover missed departure on the outbound trip but certainly check your policy as it may cover the return trip as well. If so it generally only covers delays to scheduled public transport so again this may be a factor as to whether a claim is deemed valid.

I'm not sure about the credit card, certainly if the airline defaulted in anyway you may have some protection but if it is unlikely to cover delayed flights.

Certainly check with the insurance providers on either of this products but I suspect that your best course of action would be to complain about the situation to the Jet 2, had the original flight not been delayed then there would have been no basis of complaint but the fact it was and you incurred costs because they wouldn't let you check-in may count in your favour.

Sorry I cannot help further but please keep us updated about how you get on.

Best of luck