Please do not co-locate game and down load servers. They should have separate routes to avoid bandwidth bottlenecks.
If the game servers are moved, leave the download server where it is to avoid repeating this problem each time there are new files to push out.
I'm a former systems administrator not a network monkey, but I know bad network design when I see it.
I agree with you 100%. Whats really the point of even having the download on a second box other then to save a few cpu cycles if they both have to push through another single point that has the potential bottleneck option.