Recovered from monastery tomes donated to the Targu Mures Historical Society:

Semel in Chersonesum relegatus
Propterea dic ad Khmer cælaturas
Iuvenis filius praevaricationis Jacob
primogenitus

Audio fidelium canunt
Natus est rex
Krim Jacob, vivet in aeternum
Quoniam die illa benedicta

Et Nerich tubis canere!
Audi quid dicat:
Illuc usque in sempiternum in tenebris,
Quia in die illa, quod damnatus

Ian Whitehouse has been so kind as to translate for the plebeian masses:

Once in the Crimea
Tell the Khmer carvings
Of the transgression of this young
son Jacob, the firstborn.

I hear the faithful sing
A king must have arrived
Krim Jacob will live forever
we are blessed this day.

And the trumpets of Nerich yell!
They tell us:
Crimea is forever in darkness
since that damned day