I worry that if some atevi fool tries out a human sport with home-made equipment and no instruction, and ends up dying, humans could take some of the blame for it...

I hope Ilisidi can read human emotions and see that Bren had no idea about the ship until he saw it from her balcony. Atevi don't show much emotion on their faces, so they will be really good at reading what signs there are, and absolute shock could look similar across species.