flying with that gear, been told to have batteries in checked bag, so if that bag doesn't make it, screwed???
I would
not put the batteries in a checked bag, I would carry them on.
If you carry them on and they're concerned about the batts, you can break out the documentation, and after a minor delay you're on your way.
If you check them and they're concerned about the batts, your bag will
not make it to your final destination.