I too, had questions about this, because it didn't quite make sense. However, after re-reading the rules, this is what I gathered. Since it's a special mission, you do get the normal reward, and no matter what the outcome of the battle is, both sides to get the ADDITIONAL reward. It doesn't say anything specific about it having to be the winner of the battle getting the extra reward, so I presume both sides get the added juicy goodness. That extra xp and 100 credits per player (especially in a 4 man team) really is helpful!

I completely didn't realize you had to pick the top X amount of cards in order to see what was available for you to purchase. xD My friends and I are playing, and I'm Fenn. It's been going decent for the Rebels after 4 missions. We haven't spent our xp really, and we've won 2 missions. I will most certainly have to tell my Imperial player that he needs to read up on the rules better. Thanks again everyone!