You could also use my Notorious "AND" logic gate, so it only attaches to the booster.
Keep in mind though, the physics of "Magnatize"
Magnatize ATTRACTS certain targets, so you'd have to actully have the magnatize Buff (which could be applied by the fighters...) on the Booster, and it attracks fighters, with no damage when the two collide.
Plus I don't know how magnatize acts in phase Space...
Shadow Mastiff had an idea, (I don't think it will work) is too use use the Repulse Ability "ApplyForceFromSpawner" and set the force to negitive.
But I don't think the sins engine likes negitive forces.
HERE is an idea!!
One of the vassari cruisers has a teleport ability.
USE THAT!!
Have the fighters CONTINUALLY teleport to their target. (use a Periodic Buff, with time set to like 0.1)