Sadly I only have the "prepatch"-expansion 2 folder and there is that annoying bug when you load a saved mp game the current turn that still needs to be played just gets skipped.So is my speculation that the bug was added by the patch somewhere outside of the expansion 2 folder but still inside of the Sid Meier's Civilization V folder.
Is there any way of making the contents of this folder avaliable for download by you or your friend? In the no quitters group we simply voted on banning certain units or functions, therefore as far as I know, no one has been keeping doubles of game folders.
You might have solved everything.