I don’t know if this bug has been mentioned before, or even if it has anything to do with Great Maw, but
as you can see, the oversized worm declared itself the victor though the battle had not yet finished.
What are the steps to make it happen again?
Watch helplessly as it Hungers one troop, Sandstorms the next, then Hungers another in 3 consecutive turns?
Do you have any screenshots or video you want to share with us so we can see the problem?