Just to re-iterate:
1st warning he was the last guy for over 1minute.  I made him aware of the objectives at 30 seconds because he was camp picking guys in a 1 vs 6.  It was 1 vs 6 because his team attempted to push which he did not support.  He was overwatching a flank, which is a valid tactic.  However, if you watch all the red dots disappear and don't do anything to support.  Nothing tactical about that.

Next two rounds he moved with his team and they won with him dying on a push. 

The slay round he bait/awped in the tunnels on dust.  No problem with that tactic, but if you bait/awp your whole team and its you and some other dude camping in a 2v11.  That was your poor choice of strategy.  You were prompted at 30 secs about maybe looking at the objectives, but you stayed and waited.  The person that I warned for shooting you in the head was obviously frustrated with you not using the awp to pust forward.  Regardless, I warned him about shooting snipers in the head.

The picture that is painted on a 2v11 "suicide rush" and save the awp.  Again, I waited until 30 secs because that is plenty of time to make forward movement to the objective.  Not running straight to the objective and being wiped out, but making some sort of offensive move.

This is not a situational slay.  Where I watched him 1 round and slayed for not doing the objectives.  I've observed the entire match.  He was slow playing both rnds that I had to notify T's of time remaining. That led to my slay of the terrorists left alive the second time for not making any attempt to do the objectives. 

This would require peeking to see if anyone was there.  If you would have attempted to enter the tunnels and be attacked by overwhelming cts is one thing, but you were using stand-off picking them off. 

It was de_dust...when players are aloud to not do the objectives.  It turns into 2:30 minutes of 10 players wasting everyone else's time. Just like aztec, italy, and assault.