Imho, both ransom notes are written by college educated people or well educated people according to their syntax, linguistics, phrasing, context, etc., etc.,
To me, the JBR ransom note writer sounds distinctly "feminine" in nature. Dramatic, non-specific, theatrical, emotional (somewhat angry and personalized towards JR). Suggests: Theatre or English Major and female.
Now, compared with the other ransom note: this one sounds distinctly "masculine" in nature. Detail oriented, results-driven, systematic. Suggests: Scientist, Architect, Engineer and male.
In summary, they read totally different to me.