the fact is no clear cut chronology is available as for as kerala is concerned. there are patches of informations only. medieval kerala had several small village conglomeration-states controlled by nair chieftains. one among them may have converted to islam.
i always wonder kodungallur bagawathi temple. the mudiyatam festival has all the similarities to kannagi legend. kannaki was in such a trance when she possibly reached kerala. the same trance is enacted by hindu women of kerala.
unfortunately this aspect of kannaki legend is not shown interst by tamil politicos.
another piece of history is poompuhar sambathi amman temple. it is mentioned in MANIMEKALAI EPIC. it needs restoration immediately otherwise it will not be seen in another 10-20 years at all.