Like paperpanzer I make youtube videos and have been encountering this issue for some time - maybe a month? Only mods I run are xvm, autologin (coz ASIA), mini map circles and lines, session stats and garage stats (individual on the tanks) and free cam for replays... Restarting the client hasn't helped once. *Maybe* it is since the 17.01 thing started.....
@OP - to continue to record replays I have kept a copy of the vanilla client (or in my case, the last modded client which worked) on a different drive - works well, just drag the replay file to the second WoT application and it works well. If recording a few vids in a session, the second and subsequent replay will open in the working client when you double click on it (after the initial one where you drag it) - hope this helps/makes sense.
Have attached python for anyone interested...
python.log