I would be more worried about psions in diplomacy and spy situations than combat. If I understand things correctly psions of any significant power make a small percentage of the overall Zhodani population.
Sure they could be used in direct confrontation but movies aside there is a reason elite forces such as SF, Marine Force Recon, and SAS are not frontline troops. Scouting, guerilla warfare, hit and run, and maybe sabotage but not conventional warfare.
Dropping an elite, very expensively trained, force into a ship might work in very specific circumstances but you would need the very specifically trained force in the right place on a ship that manages to match direction precisely enough to do the teleportation and then they would need to take out the ship then escape with them knowing the destination and still matching vector.
That is a lot of risk to highly expensive troops for marginal gain. Far better to use them for surgical, carefully planned strikes or intelligence gathering. Trained psions as a military force are truly a potential game changer, but they can fall to a grunt with 6 weeks of basic training and an automatic rifle like anyone else.