I was able to complete the final mission without using a judas warlord. After building a small base with two mines at one mineral deposit (for faster BMUS) I constructed three heavy artillery turrets at the left of the left pillar and three at the right of the right pillar to create a heavy battlefield just in front of my base. In the middle (between the pillars) I had some reapers and knights (just a few) to prevent the enemy from destroying the turrets. In case this actually happened I had a builder constructor at each side to repair or build a new turret quickly. In some cases I had to use First person knight to circle in the battlefield to keep the enemy machines busy firing at me, while the turrets took them down.
After the mines got empty I used of course some scavengers to pick up BMUS. The attacks from the west shouldn't be a problem. With me holding on the enemy slowly decreased their attacks, making it possible to build (with the picked up BMUS) an army of knights with three heavy plasma cannons. After a while I started attacking with I think maybe 20 of those knights I was quite easily able to destroy the enemy room bij room and finally destroying the controller.