It’s really not circumstantial, man. Everything I mentioned are ways you can make it work. It doesn’t need to all fall in line. The guy doesn’t have to be solo, you can kill all his buddies first. You have 6 full turns to get back to him with cryoorb. I don’t get this 12 seconds thing, you stay in turnbased mode still. Cryoorb much like nades can only miss within 3 tiles so as long as you target the tile the enemy is on he will still get some shards. I’ve executed this more than plenty of times. It’s honestly not complicated. Cryostasis lasts up to 6 turns and stealth only has a 2 turn CD. Even without lti or any chills you delay the enemy for one single turn post breaking stealth and you can do this.
Edit: I recorded this really fast. Pretend the first 2 kills are from far away with aimshot and snipe while taser acts like the spacing you use to delay the enemy on the first turn. I used impale because it can be directly substituted for snipe for the comparison since they have the same CD. This works even with multiple enemies but my initial statement was "You basically can’t lose a 1v1 assuming you the survive long enough to cast cryostasis".
https://www.youtube.com/watch?v=o6Kwv2wRm0U&feature=youtu.be