I also need to share my opinion on this and have to say: I have problems to buy his story.
I see only two things we can take as known facts (with good level of confidence):
- He got vaccinated with Sinovac (he presented the certificate, so very likely that's how it was).
- He has an attitude problem (based on his behaviour and his way of dealing with his own mistake I think it's a fair conclusion).
I have received my first jab of Biontech and it was just a flawless experience and all seemed very well organzied. I wouldn't categorically rule out that as a result of a series of human failures it's possible to end up in the cabin where you receive the jab without a valid booking. But at that point the nurse is entering your ID into the system - and it sounds extremely unlikely that in their IT system there is no connection at all between the booking record and the record for the vaccination. That sounds like a too obvious design error to believe, where the rest of the system seems very well planned. It's also an important and obvious security check to prevent nepotism (keeping in mind that HK is very unique compared to the rest of the educated world - in the home country of Biontech for example people under 80 would bite of your hand to get a Biontech jab these days, whereas in HK they can't even find enough takers for the first batch...).
It's possible it all went down as he said, but sounds extremely unlikely thinking about all details. I would say it's also possible that he just booked the Sinovac jab (maybe accidentally) and everything was processed by the book by the organiser. And for whatever reason he just made up that story. We will probably never know what really happened, but something like this is to me a more likely explanation than his one. That all being said, I'm sorry about the cancer and wish him a good recovery.