I'm sure another TF2 admin has tried to view the replay files stored on his server, to investigate a cheater. But I can't figure out how to do that myself or find any instructions about it. Isn't it possible?
IIRC, All you need to do is download the replay file from your server and place it in your TF2 replays directory. You should then be able to view it from the TF2 replay editor. (A restart of TF2 will likely be required)
Important: Make sure you backup your other replays -- if there is a name conflict, you could lose your own replays.
Have you tried this? http://didrole.com/Replay2Demo/
OMG it just works! You open the demo player in tf2 with shift-F2 an load the demo. Press shift-F2 again to regain camera control.
and stop answering your own questions, stupid.