If fans are using the Covid passport on the NHS App, it’s just a scan of a QR code.
It's not just a scan though: the season tickets are on the phone too, so you'd have to log out of the app and onto to Google Pay. It's only going to take about three seconds to do that but that will quickly mount up. Say one thousand people go through one automatic gate, that's 3,000 seconds - that's an 50 additional minutes to cope with. And that's assuming that the wireless network at the Amex can cope (and judging by the amount of time that there's no signal, that's highly doubtful)
The only way to do it is to tie double vaccination info to the ticket in advance