AIBU to think that the Ticket Inspector was a 'Jobsworth'?

On the other hand you get customers who are really lazy and feckless. They order international goods. You send them a tracking number and its too much trouble to enter it onto the postal website of their country. They keep coming back to you (the seller) for information as to where it is. Eventually you have to tell them that the package is at their local depot awaiting delivery and there is nothing more you can do to help them.

Yes the ticket inspector was doing their job, they possibly could have got into trouble if they hadn't done so.

Sadly I agree everything seems more complicated and the customer doesn't seem to matter now.

Unfortunately she applied the rules. The only thing you can do now is apply for the refund when your card arrives. Bit of a hassle, but I find most things are a bit of a hassle these days. Try speaking to an actual person on the phone! It’s often impossible. I don’t want to talk to a bot, but there it is.

Surely she was just doing her job though?

By your own admission the email you had stated that it could not be used as proof of a card.

I don’t see what telling her off would have done for you except make the situation serious.

You can get the money back. This seems a none issue?

I think she could have waived the rules, even if it meant you providing more "evidence" within the next few days.

Them are the rules. Personal circumstances don't enter into it, and compassion won't count either.
Having said that, I'm glad your son had a favourable diagnosis from what could have been devastating.

The email could easily be fake, she was just doing her job. Fare evasion is rife.

I once got into an argument about a Senior Railcard.

I was travelling about a week after renewing my railcard and I had it with me. A ticket inspector rolled up and demanded to see my ticket so I handed him the ticket and railcard. His face lit up and he said "This railcard went out of date over a week ago". I politely pointed out that it was for the current year and not last year and he blanked me.

He then asked a group of rather stroppy young men for their tickets one of them said "We haven't got tickets. What are you going to do about it?"

The answer must have been nothing as he moved swiftly away down the carriage.

The railway is a domain on its own with regard to the law and even policing. It is a throwback to when railways were first invented.
I think they are always on the lookout for any way they can make extra money. And they are quite intimidating. If buses operated with this same attitude, there would be quite a to-do.
Some of the journeys I’ve made are excellent value for money and some are outrageously priced.
There is no balance.
I don’t understand why the ticketing has to be sooo very complex either. Should it be stressful just choosing a ticket?

She was applying the rules. She probably has no discretion in the matter. You could have been producing an email to someone else or a fake for all she knew. You can get a refund. I have seen enough fare dodgers to know that ticket inspectors have a hard and sometimes dangerous job.