Orientalism, Aramaic and Kabbalah in the Catholic Reformation: The First Printing of the Syriac New Testament is a 2007 Brill book by Robert Wilkinson. Pages 68-70 provide some insight into the background of the printing of the 1548-9 Ethiopic (Ge’ez) Bible. Evidently, the printing was based on a single manuscript that had recently arrived in Rome from Ethiopia. In a footnote, Wilkinson points the reader to Metzger’s “Early Versions of the New Testament” regarding the deficiencies of the manuscript.

Metzger, at p. 299, points out that the Latin translation in Walton’s Polyglot was repeatedly criticized: “its Latin rendering has more than once been excoriated as being far from accurate.” (p. 230). “Novum Domini nostri Iesu Christi Testamentum ex versione Aethiopici interpretis in Bibliis polyglottis Anglicanis editum ex Aethiopica lingva in Latinam” by Christoph August Bode (aka Bodius) (1753), may provide some improvements to Walton’s translation, but only appears to address the four gospels (link).

Evidently then-Cardinal of Sana Croce, Marcello Cervini (later Pope Marcellus II), was a patron of the printing. The colophon “seems remarkably to claim that Cervini could read Ethiopic. If this were so, it would suggest an involvement in Oriental Studies beyond that which has been previously imagined.” (Wilkinson, p. 69, fn. 23)