Ohanzee will reiterate this on his IP, but if they start fleeing, Doc can still disable the vehicles so they won't get far. But, it couldn't hurt to disable them in advance, just to be safe.
But additionally, making sure they don't get a call out for help or that Doc Wagons don't activate can also be good, though the latter likely wouldn't pose a problem as the fight would be done and we'd be long gone by then. It has the advantage of having medical attention arrive to possibly clean up the Natelys.
But, yeah, unless anyone else gets to it first, Ohanzee's free action for his IP will be to message "Don't let the vehicles get away!" or if that is too long, "disable their cars!". Ohanzee doesn't know about the Doc Wagon contracts and so wouldn't comment on them. But through Wolf he's aware of the Bulldog re-positioning and when it first started moving, he was probably concerned they were running for it.