Maybe the trilobites are having a bad day, or maybe there's just too many people around for them to be comfortable, but Darcy and Bingley fail to display any significant behavior other than a fondness for offered fibrous material. They have no interest in the Coral plants' shells, and unfortunately? They are just not smart creatures all around.

Due to a lack of information provided about your taming methods (and your low roll of 17), the Darcy and Bingley remain free spirits and (currently) can't be tamed, etc.