Can Slann be stomped or thunderstomped. Think that probably they can but my opponent didn't think they could because of the plaquaine. He reasoned the same rule that stops the Slann taking transformation of Kadon would mean that he couldn't be stomped. What do you think?
That would be nice. However, the only things that prevent stomping are being a unit type of Unique or being monstrous infantry. The slann is neither of these, so it can be stomped. I agree with your friend, you would not think so with the palanquin though. If you want to be fluffy about it, you could look at it as the slann falling off the palanquin when something tries to stomp it.