Please also explain how the digitally created green background was imported from the future to 1961, when there was no digitally created anything until the 90s.
Also explain why anyone would scan when a photo would not only suffice but be more believable.
just saying.
The answers to those questions are irrelevant because nothing will satisfy you.
If you’d use your brain, just a little bit, you’d answer your own questions.
The green background is not from 1961. The cert is printed onto that paper from the original which is in a bound book, which is evident from the curvature on the left hand side.
To the naked eye, it does look as if the words stay straight. I held up a piece of paper and the letters do, indeed, curve. So that's OK.