For me, there is a whole range of possibilities how the MS was created.
Some of these possibilities have many precedents, others have few.
The first question could be whether the scribe and the draughtsman were one and the same person.
It would be more 'typical' for them not to be the same person, but precedents for both exist.
The quality of the drawings also isn't such that we see the work of a trained artist (or artists).
Furthermore, both the writing and the drawings are 'unusual'.
This certainly has an impact on how the MS was conceived.
It may have been entirely someone's personal creation. Someone who had never seen any other MS's. I believe that this is extremely unlikely.
It may have been largely based on MS's seen either in the past or the present.
(The scribe most certainly was not illiterate).
It may have been copied from MS's available right there and then.
Such MSs may or may not have been illustrated.
If it was inspired by other MS's, these would have to have been available during the scribe's
lifetime. The many identifiable examples of inspiration and style that have been found even
recently are all from MS's that would be readily available all across Europe.
(Note that there is one intriguing counter-example of this, that requires a closer look. This is the
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Now one can entertain the opinion that the MS was copied from something that
was many centuries old, possibly even more than a 1000 years, which had not
been copied by anyone else in the meantime.
This is not impossible, but it is not the most likely of all scenarios, and would require
quite some solid evidence before it can be called convincing.