It's possible to cut through it's armor, but...we shouldn't chance it right now. We need a way to hit under it, like you did to get out. [ Easier said than done...again, if it was him, he could cut through. Hmm...even if it was over-sized, it wasn't like it was made of metal. ]

It's head should have a weak point too. That'd be easier to reach than the underside. Go for that.