Giant,
ok, this is very strange... I did a quick test on my PC, and it was working normally.
I don't see how the Coop doubles could be slower than the Competitive one.
Did you install a Mod that would show country flags ? If so, try without it.
If not, maybe uninstall everything & reinstall everything ; this helped other players with lag everywhere, so I'm not sure it'd help you with lag in that specific setup.
Erik5300,
"0Ssid-short strike" is the shot decision for the CPU, so if there's no CPU, it'll never change...

For the human players, check the changes of "B0c / B0c" ; 0 = button num ; u/c/d = up/center/down (up/down are inverted when on bottom of the screen)