Sarahs statement on the pproblem:
I think she was correct partially, some of the reward did not show up in the final screen, However, there is still a large amount missing. Since they changed the system its become more noticeable when the XP amount is off.
@Sarah247 Would you be able to have a quick look into this?
Seems hard/insane missions lose XP and coins. and can be as much as a 40% loss of earnings on the Big Boy mission last time i checked.