having had a day to settle down and re-watch the match sober, i'm in a better position to analyse the game rather than joining the mob with my pitchfork.
the second try was bad too. ignore the 6 again call reversal. coaches demand accountability from players and Ricky Stuart would've been livid at the breakdown of fundamental process on the Tedesco try.
After making a good one-on-one tackle on Cordner on the 4th, he lays behind the ruck. no other Canberra player takes up the mark so Keary has the opportunity to scoot from acting half and make a play on the short-side where he can exploit the Roosters advantage. With Leilua out of the defensive line and no markers to impede his run, Keary runs the gap between the the stand-in 3-man (Bateman) and 2-man (Rapana). He draws Rapana, passes to Mitchell who draws in the wing defender (Sezer), who gets the flick pass out to Tupou. rest is history.
Raiders picked a bad time to switch off, i.e, Keary near the ball. Perhaps if it were Mitchell, Tupou, anyone else at acting half, the result may have been different. Keary is going to exploit anything you give him.