You should check whether the characters used in the VMS – e.g. the typical "R" r and the "8" d , among others – were already typical 400 years earlier... as far as I know, the rotunda R didn’t emerge until the 12th century and only became widespread and standard in the 15th century.
And the 8, as a "d", I believe, was only written in a similar way with the Bastard typefaces, so also only in the 15th century. But I am NO calligraphy expert...
And the 8, as a "d", I believe, was only written in a similar way with the Bastard typefaces, so also only in the 15th century. But I am NO calligraphy expert...