I would get a small strike team to take out various dars along the way, not just the dars on route as that would make it too obvoius, get some ponies with rox and then they can grab for alt again.
See if there's anyway you can do something about the dar from HT just for this mission? Or maybe try and sneak along at the maps edge? Have the buffs launch from different bases to keep dar small and then maybe rv somewhere along the route? Have the escorts doing the same thing perhaps?
Also try and get a "Gentlemens agreement" in place that we nits or bish only up LW crates for the run,I'm sure if you implemented some of this then you would have a rock solid mission going. Dissapointing to hear about the ponies, but that's what to expect when you stick a bunch of them on the mission.
I like Talons idea RE: more jugs, that would prob flesh out the noobs more and so you would know what you had to work with. Another idea I had is that I'm sure there are great buff drivers, pony drivers and Jug drivers from both nitland and bishland who would prob jump over to rook for the next one, Don't see why not as you can switch back after an hour or so, the LW drivers could do the same from rookland?