Just to be clear, I'm game to engage the goblins and try to rescue the sacrifices if we can come up with a very good plan to do so, but Bardhyl will need some convincing.

I'm fairly convinced that we can't actually win a straight up battle, even if we can start with an ambush, but possibly a shock and awe first strike can cause enough confusion that we could rush in and grab the sacrifices. I suspect fire - and lots of it - would be necessary for us to have a chance though (both for the grabbing and the escaping).