Whenever you fire two wire-guided AT missiles from the Titan MPRL Compact launcher, the second one always goes high, and will likely miss the target.
I noticed this when playing KOTH. I would try to hit a target at long range, and my second rocket would always miss. I would have to aim under the target in order to hit it with the second missile.
Fire a missile.
Wire-guide it to the target.
Reload
Fire a second missile.
Wire-guide to the target.
I just tested this in the editor. It doesn't go much over but if your aim is more on the top of the vehicle the missile can go over.
1km aim center of T-100 still always hits. Is your issue much worse?
The last time, I was aiming at the top of a tank, at the turret, and it went over.
I'm also not sure about the distance, either.