It is very unlikely that you will run into a fire wand... or any wand in a chest. You get random stuff... so if you want a fire wand, you usually have to buy it.
... It very much depends on your build. You need magic perk before you can use it.
Ah yes... it's a scripted event without any leeway.
Yes. By sneaking around and bonking them on the head as you sneak out with Elise... but there isn't really a point to not murdering all of them.
