Totally disagree. The R is in position to see if the attacker was blocking line of sight—it’s his miss, not the AR’s miss, as the AR doesn’t have the angle to see if the attacker is blocking the GK’s vision. In any game, the AR and R should be communicating. The AR should be telling the R that the attacker was in OSP, and the R should be deciding if that blocked the GK’s vision. With comms, that’s a convo over the comms, and without them, it’s time for the AR and R to get together for a quick chat on the touchline.