The classical Okinawan poetry collection the Omoro Sōshi is written (mostly) in Hiragana, but the phonetic mapping of the characters to sounds seems to be different to their standard mapping.
For example, the title "おもろそうし" was presumably (according to the Okinawan-English Wordbook) pronounced more like /u.mu.ɾu u.soː.ɕi/.
Short /o/ and /e/ in standard Japanese seem have been shifted to /u/ and /i/ in Okinawan respectively, and moreover, Okinawan phonology seems to distinguish between /ɸ/ and /h/, and seems to feature glottalized vowels, approximants, and nasal consonants, all of which are not distinguished according to the standard mapping of the hiragana.
So my question is, how did the hiragana orthography used in the Omoro Sōshi correspond to the pronunciation of the poems? And did it adequately map the phonetic inventory of the language, or was it defective in some regards?