I think we are in the " eats shoots and leaves" territory
" Lower quality Greek work" can be interpreted as " lower quality, ie Greek, work " or "lower quality work that happens to come from Greece" .
I am sure Valjhun meant the latter (and that is how I red it): it has Greek motives but this particular specimen is not a museum masterpiece. No condescension toward Greek workmanship in general was intended.
Would be a pity if a grammatical ambiguity caused bad feelings between the two of you.
As to the inscription... I had a Yataghan with a bizarre inscription that nobody could read. Then somebody just read it as a crude script of Osmanli.
Don't despair, somebody will help. I do not believe for a second this is a mumbo-jumbo.