My experience at Bang Sue (Oct 19) was much more 'user friendly'. After completing the same brief form as prior to the first injection, I was directed to a vaccination point (doubles as data entry). A mere 13 minutes after walking through the door (just before noon), the job/jab was done.
At the vaccination point, I enquired about a certificate and was directed to an adjacent bank of PCs - a little more data entry and a certificate was readily printed.
On departure following the recovery period, I was asked if I felt well, told how to treat any consequent fever, and asked if I needed a vaccination certificate.
Needless to say, the certificate gives the fabled 13 digits, aka the Alien Registration Number. I didn't use the QR code but, instead, entered the ARN into the MoPH app, entered the OTP, and provided a password - a 6-digit number. BINGO!
The whole process ( both doses) was extremely well organized and, sorry nay-sayers, reflected very favorably on Thailand and the Health Ministry - nothing short of brilliant!