Non-crit tesla damage gets evenly distributed among tanks it is targeting; aka if it is hitting 2 tanks at once each tank will only take half damage (Unless it gets a crit). Likely the reduced damage was because the shot was spread among your entire team rather than anything else. I don't know for sure if there is an augment for this, but considering it from a balance standpoint it is so egregious that I just can't imagine the dev team creating such an augment so I'd guess it is a cheat.