I'm sure that this is covered somewhere in the rulebook or errata, but I can't seem to find the answer for the life of me.

In short, if a charging unit (A) can make contact with an enemy unit (B) that's already engaged in combat with a third unit (C), but "A" can't close the door due to intervening terrain, what happens?

The Bretonnian player insisted that both my Saurus (B) and his smaller unit of Knights (C) had to swing around in order for his Death Star unit (A) to enter the melee. Can entire combats rotate for the sake of "closing the door?"