וחי בהם. However, if the Israelite does not observe these statutes the souls violating them deliberately will be cut off from membership in their nation, i.e. will lose their life in the hereafter (verse 29)

מולדת בית או מולדת חוץ; both legitimate or illegitimate, both unmarried. This appears to me to be the plain meaning of the text.

לצרור, similar to Samuel I 1,6 וכעסתה צרתה, “she deliberately angered her competitor Chanah, also wife of Elkanah. When a man has two wives, each is considered as a hostile competitor, צרה to the other.