Ambush and backstabbing

How would you handle ambushing with DA's moves?

I have a Troll Killer having maneuvered to get in a high position behind a bounty hunter and about to jump down, blade first, assassin's creed style bind and on top of her enemy. In vanilla AW a clear case of going aggro.

In general, as I'm reading the new moves, I'm leaning towards rolling to hold steady to get into a position of backstabbing and then just doing weapon damage or even just kill the victim straight out. Then, if the enemy still lives and maybe strikes back, we would be in a going into battle situation.

In this particular case, the Troll Killer has held steady climbing to the position above and behind the bounty hunter, and she is wearing her bunny cap, allowing her to go unnoticed by her enemies. What now? Jumping down and sinking her blade in the bounty hunter seems like it should mean rolling for something, but if that roll is holding steady, should the bunny cap mean she can leap within sword range without a roll? Nah, don't think so. I think I'll go for another roll for holding steady for jumping down, blade first, and if that succeeds, just have the bounty hunter take sword damage, probably killing her outright.

Am I missing somthing?

If the Bounty Hunter hasn't noticed the Troll Killer, I'd say a Hold Steady roll just to keep their nerve and wait for the opportune moment. 10+ outright kill, 7-9, deal weapon damage and/or introduce a complication (IE: A hidden gorget around the neck, strips of metal under the coat - unexpected armour), 6- either alerting the Bounty Hunter to the Troll Killer's presence, a miss, or deflected by armour.

Yeah, that's more or less how I did it.

Still curious about how other players have handled it in actual play, though! I guess ambushes aren't that uncommon, I mean.