If the jockey falls off the carnosaur then it'll likely not follow the lizardmen anymore and be a neutral threat
I have two old Lizardmen books laying at home. Just to get an idea of their old lore. Apparently there were single Carnosaur models. Were they simply cheap beast models without the rider, and for a lower cost?
Would be cool to have some models have a few lesser attacks when you feeld them without a rider/riders and have them be a bit cheaper cost points. Like the carnosaur,bastillodon,stegasaur and troglodon