When Ralph and Barry board CCTA405 at the impound yard, the interior advertising panels are lit, but the bus is not running.
As in the previous appearance of the dinosaur, a skeleton just cannot move or run. All the joints have oil seals between them that keeps the bones apart enough so that the bones can articulate independent of each other while moving or running. Also, the tissues at joints keep the bones nearby so that movement is within the comfortable range of the oil seals. If there are no tissues and no oil seals at the joints, the first minuscule movement will separate every bone and the entire skeleton will fall like a house of cards. So, all that movement and running of either dinosaur is impossible.