Hey Slojoe,
From what I've read so far, you and your CC are getting the extra 2% (27 XP for 1345?). The bug is with the XP display at the end of the game ... probably just an oversight on WGT's part.
To check it, look at your XP at the beginning of the game and write that number down. After your completed, check your XP again and do the math. It should show that you are in fact receiving the extra XP.
When our CC gets to that level, I'll be sure to check this ... cuz I'm just that way.