I know you haven’t been vaccinated but have you seen one of these NHS vaccination cards? If they were ever intended as vaccine passports then they are the shoddiest job ever. The only identifier is your name, which, on mine is written by hand, and then the dates and ids of the two vaccine doses. On mine its been typed on but on my wife’s it is again hand written.
It would be the easiest passport ever to copy, change or make up a fake one from scratch. In fact I am concerned that immigration here won’t accept it as proof of being vaccinated, a requirement now for both residents, citizens and any other allowed visitors, to leave or enter the country. I am going to have to ask my UK doctor to issue me a letter, for which the bastards charged me 15quid last time and I had to write it for him to sign, so I can be sure I can get back here.