http://www.ibisgaming.com/forums/sho...Links-to-Demos
That is the link to find the demo you need. Source TV records all maps that are played. It only stores them for a few days though. They have a Time/Date stamp. Honestly not often does it go from Sorrento to CS Assault, shouldn't be to hard to find. Save the Demo to your cstike folder then view it in game using Demoui in console. Ensure that you find what you want.
You did the right thing by reporting, whether or not punishment is handed down, it gives the admins a view as to how the server feels about certain actions. He is allowed to choose the map he wants though. Doesn't need to ask or listen to the server as a whole. Its one of the perks for having to babysit the server. For example if I am senior you will NOT play Sorrento hardly ever. And never with chutes!