Cadet leaves first, because you have to resolve the whole “remove rune->bounce thing” ability before killing the Archon (and the Cadet will come back after that too)
There is no “correct” answer to one of these, but if you legally kill the opponent this turn, that’s good enough. There might be other answers as well.
In the original game, I’d say they were more of a plan that went right. I was putting a ton of pressure on early, and had just built my tech 2 while breaking his. He played and maxed Oni, and on my turn 5 I chose to break his tech 2 again rather than kill Oni. From that point, he was able to lock me down for a couple of turns with Art of War until I was able to assemble a way to kill Oni. Then the game went on for a couple more turns after that.
That is really cool. I continue to be surprised by what is possible.
Solution:
Take off all your clothes
Having played some base race Red before, my gut instinct was that moments peace just wouldn’t be enough. I have been looking for a way to burst down the base but it looks like Caphriel beat me too it 
I was too sleepy to finish writing this last night. caphriel beat me too it. 
Tech 2 drill sergeant
Get Paid $14
Fading Prynn to 3
Ebbflow Archon draw 1 $6
Ebbflow Bounce and play a cadet 5 times to draw entire deck, then bounce play OC once more to reshuffle and draw DS
Prynn banishes ebbflow and then dies dealing 3 to Basilisk and returns ebbflow to play
Midori kills Basilisk safely
Play first drill sergeant and draw the other drill sergeant and get 1 rune. $0
Bounce play cadet 7 more times killing ebbflow and getting 15 total +1 runes
Move all runes to the cadet that hasn’t done anything, swing for the kill.
noob player missing obvious lethal