What is in your opinion the right way to check whether you have actually graduated at Oxford and what grades you had if not asking for the official documents that contain this information?
The right question is whether a guy who is over a decade out needs to do so, as the degree is not evidence of competence when it's been that long.
Of course it's possible they went with getting paperwork rather than using the interview as an opportunity to ask relevant questions. Interviewing is hard.
That's what they did, so why are you complaining? (Note that these documents are called Zeugnis in German, which translates to certificate, so maybe something got lost in translation if you think your university certificates are the wrong documents.)
I also disagree that an academic title earned 10 years ago is irrelevant. Having graduated with good grades from a top school signals a lot, even if it's been a while ago.
So rare in the states. I have as far as I remember, I never had to prove I graduated anything. Some companies do background checks, maybe part of that is to call up the unis and ask if I graduated? No idea what the uni makes public, but I have definitely not had to hand in transcripts or anything.
The right question is whether a guy who is over a decade out needs to do so, as the degree is not evidence of competence when it's been that long.
Of course it's possible they went with getting paperwork rather than using the interview as an opportunity to ask relevant questions. Interviewing is hard.