OP,
Did you forget the first two and half minutes of the round when Gilbert was on the cage wall with a high guard covering up as Khamzat unloaded 20-30 strikes on him with no response. The fight could have been stopped then and there. Gilbert got the better of Chimaev during the second half of the round but it was not enough to make up for Chimaevs dominance during the first half of the round. Clear 10-9 round for Chimaev in the third.
Also, why shouldn't the first round have been scored 10-8? Khamzat knocked him down and reigned down elbows as Burns covered up and the fight could have (and maybe should have) been stopped then and there. That was a clear 10-8 round in the first for Chimaev.
Not a robbery, the right man won, even if a lot of bettors +700 Burns DEC tickets lost (i was one of them).