That's what I first thought about thrust adjusters, but it just says to tighten to specified torque.
They're probably expecting that if the specified torque isn't aligned, the there's frame damage and the bike isn't safe to ride.
My take on this:
"Thrust angle" in 4-wheel (RWD) alignment is the angle between a line perpendicular to the centerline through the rear axel and the centerline through the vehicle (if that's confusing, Google image search). In a motorcycle, the rear wheel can be adjusted to change this angle. But if the thrust angle isn't the same as the angle between the front and rear sprocket, there's lateral strain on the chain. Ideally, when the two sprockets are aligned, the thrust angle will be 0. If the two sprockets aren't aligned, the engine itself will need to be shifted, or you'll have to deal with a non-zero thrust angle. Assuming the frame is true, and the swingarm, factory torque specs on engine mount points would ensure 0 (or close enough) thrust angle when sprockets are aligned.
So, that's really the only thing I could guess they mean when they say "thrust adjusters." If you need to change it beyond factory spec, I don't think you'll be able to get any significant accuracy without some sort of laser alignment rig. Honestly, I'd say unless you've gone down on the bike, leave it stock, adjust by the swingarm markings, and call it good. If you have gone down, chose wheel/thrust or sprockets. Either being off will have negative drivability impacts, and increased wear (tire vs chain). Personally, I'd go with risking increased tire wear over chain. I've had a chain break and drive through my crank case, it's a bad day. Tires are easy to inspect and don't have a sudden catastrophic failure mode from lateral strain.