That letter is simply a computer generated letter, similar to the dozens of computer generated documents some of us make every week. It’s easy to make such a letter... most of the form already exists, and all the secretary has to do is insert the proper name and dates; the rest is done automatically. But this particular letter has been Photoshopped... hence the irregularities.
There is no scanned original letter from 1976. I doubt that the U of Milan has any records pertaining to A. Rossi at all. His language and behavior just aren’t consistent with those of a college educated individual.
It's not like all of us don't know the steps for working up computer images.
My favorite had Hillary Clinton with the Pope and he had his hand on her bottom. It had to have started with a picture of the Pope and of HIllary ~ with both being digitized.
This letter starts with someone scanning something with a cheap bar scanner.
BTW, some of the contracts Rossi worked on (according to the Army and other independent sources) required at least a Secret clearance.
His accent is no worse than that of Henry Kissinger.