Jaheira won't become full fledged companion after battle at Moonrise. If I remember correctly there is a check to convince her to help you rather than Harpers. She will become fully controllable NPCs, but not a companion just yet. She is fairly useless in combat, as she has very few skills to utilise. Still, much easier to keep her alive.

Resurrect, unfortunately, works only on companions. So speculative to be companions (like Jaheira during Moonrise battle) likely doesn't count.