the basic vocabulary is as a whole a good marker of common origin for a language family ; but when it comes to the most basic one, as the family/filiation words, they can be shared with other families themselves issued of a previous larger group of languages. Specially for the meanings of 'father' and 'mother', whose origin come from onomatopoeas I think (baby language?)
cncerning 'zana' it evoks me 'zhena' woman in Satem tongues; was Elamitic a language with 'satem' tendancies? I know nothing about this...