I assume is a glitch, but the vassal setup for this first scenario does not include the Armored Brigade of the 1st Corps in hex # N2819. Only the 1st Brigade Infantry is placed. Is the whole corps placed as per the scenario instructions or is the vassal correct and the armored brigade is not on the setup ?
If you mean the "Seoul Train" scenario, the instructions in the Game Specific Rules are correct. All ROK I Corps units (except the HQ) should be set up.