If Arianna had been awake at this point, she would have been shocked at the sheer number of escorts behind them.
After they left the scene, Marcel made sure their vehicle was heavily followed in case Elijah was suicidal enough to plan an attack on them. He lost his chance at the Red Gang's turf, he could attempt one here.
Knowing Arianna was the only one Elijah truly needed, the amount of security guarding Jemery's car was less compared to theirs. Although Elijah could try to attack and shut Jeremy up so he could not risk secrets about him, Marcel highly doubted he would do that.
Why would Elijah bother risking his life to shut up the witness when the girl - who was the prize - wasn't far away? So yes, Arianna remained Marcel's priority.
