Unfortunately, there's no way to track any of this.

The only, possible, higly-unlikely, uber/super/duper remote chance is if (and that's a big "if") you happen to stumble upon that particular lander's Soldbuch and his rifle's serial number is recorded in it. FYI, not every weapon's serial number will be listed in the soldier's soldbuch.

If your luck is running like that you're better playing the PowerBall lotto.