I get the impression this level is intended as a speed-run of sorts. What I don't get is that if I put an enemy to sleep then stamp on him, he wakes up and sees Eivor, voiding one of the objectives, then fights Eivor (so gets stomped without dying). Not the first pair, they wake up, stand up, don't see Eivor right in front of them, then die. It's a bit annoying as several times when I have tried to use Eagle Vision I've stomped on a sleeping guard, so ruining the run.
Is this a known bug? Is this as-expected behaviour?