That's excatly what happen to me last year , i was getting year long multi entry visa from embassy in Yangon, so now i have year long extension from CW. they need to know if you have enough Thai staff or not and more .... it is getting harder now for that way.
can u not extend ur hubby extension of stay here in Thailand base on WP. if doing so u would be getting dependent visa under him. much easier i think. lets hear from other too.
if you have wp then u take requirment document from ur company to get extension of stay 1 year. can do at ur local immigration. ask ur HR or company team for document