Can the Allied Player move the counter out of the surrender box by playing a card? If not, then at the end of the game, the Political Will might be driven to 0 and then auto win for the Japanese Player. It may be hidden somewhere, I don't see the -2 US PW penalty in the South Pacific RB.
I am not near the rules so I will check, but once China surrender it cannot unsurrender. As far as the minus 2 it is the penalty for the surrender. If it's not there it should be,