here are further details on the text, confirms what you have found Pat
By a learned Irish cleric. Howlett, op. cit. 48, tentatively suggests Israel Grammaticus, fl. 947 Most of the text is in Latin; much in latinised Greek, some in Hebrew.
77 Greek words in latinised form, of which 9 are hellenized Hebrew.
17 words in Hebrew, 9 of which are in hellenised form.
Cambridge, University Library, MS Gg.5.35, folio 420a-b, saec. XI med., from St Augustine's, Canterbury Saint-Omer, Bibliothèque municipale, MS 666, folio 43-rv, saec. X, from Saint Bertin
Saint-Omer Hymn