As for the underclocking - There are 2 reasons why I'll decline this:
First of all, you didn't include atleast two 2 screenshot showing his ping by pressing tab.
Secondly, there was nothing suspicious at him. His movements were perfectly fine except of the last round in Mansion(could be random spikes).

As for the shotbotting - I'll just give my honest opinion, he looks like a decent player. Also there were some moments when his crosshair was on his enemies and he didn't shoot (on both replays).

Therefore I'm sorry to inform you but I must decline this report.