Thinking better, trying to play with new magic in a combat situation where the exact strength of the enemy is unknown is a bad, bad idea. We should figure out about the unravel vitality necromancy (and/or some that simply destroys vitality instead of grabbing it and keeping it in a usable form), but not now, later on zombies we know we can take without any problems in a more controlled situation than this.
Number 4 is out as well, using zombies as a search party is an even worse idea right now. It ranks pretty much as "hey, let's reveal ourselves as necromancers". IF we do so, we must do after we are well established as a hero, so they might stop to give us the benefit of doubt before going for the torches and pitchforks.
I'd say, a mix of 2 with 6, Command Undead on one of them, and let the zombie plus Omo deal with the other two. Other than that, if Omo seems to be on a tight spot, jump in with Steal Vitality, but if he seems able to, let him handle it with only a single zombie of help.
If we miss the kids and they actually see it, bullshit it as secret elven powers and that now they are keepers of the secret. Hopefully if they start telling tales it will be dismissed as inflating the whole deal.
Do remember to tell Omo the plan btw, so he can actually expect one friendly undead (to be destroyed post battle, we can't afford to keep it around for now).
And heavily changing subjects, we need a better income source later. Looting ruins might be one of the best options if we can. Weapons, armor, potions, all this is kinda expensive.