Where did this come from?
In any case if the pseudo-data online is correct they couldn't be used for any longer than 20 minutes before they needed to cool down, so they would have to either have very specific and quick goals for them to accomplish, or they would have had to somehow hold off the forces with their older models while the Zam's cooled down.
If they could have I would have expected the battle to end in a stalemate, and possibly an uneasy peace worked out.