I've always believed the car and where it was, and wasn't, found is the missing piece. I agree it was left there by someone who got the description of where to leave it wrong. Which begs the key question, why bring it back at all? The answer, to me, is to make it look like Jennifer disappeared from her residence, not from wherever she actually did. Following that logic, wherever she was must link back to the perpetrator. So she was abducted either from where she went the night before or that morning from work or from a stop on the way to work. Either way, the perpetrator knew her, and whereabouts she lived. If from work, it may have been premeditated, especially if they were the only ones there. Perhaps someone 'forgot' a file at home or other location and she drove them together to get it, never to be seen again. Or it started innocently, and hit the fan when they reached the second location.
I don't think the person on video is directly involved or even knew the significance of the car or whose it was. It sounds like a "hey man, here's 20 bucks to leave this car at the condos by the xyz. I told my xyz I'd drop it off, but forgot I have a dental appt, final exam, visit to my PO, lost my license, etc. and can't do it." The driver followed through because he knew he'd see the asker again. The driver wasn't thinking "I wonder if I walk down the street the camera will catch me incompletely and I'll be the luckiest POI ever." He either wasn't aware of, or wasn't concerned about the cameras; didn't realize Jennifer lived there, and likely didn't know there was a Jennifer in the first place. Not everyone follows the news, and seeing a piece (or poster) about a missing woman wouldn't mean anything to the driver unless it showed the car. At that point, he's not going to the police for fear of arrest, blackmail, deportation, the perpetrator, losing his spouse/kids/job, or any combo thereof. It's possible he doesn't even know he's on a video. If he does, he's no longer in the area. I'm using "he" here, as I see a young adult male, but you never know.
I haven't seen the pizza video so not sure what context it's in, but a couple of pizza delivery drivers who knew each other peripherally would make the above drop off possible. Yet, Jennifer wasn't stopping by for a slice at a closed pizzeria before 9am, and a delivery the night before doesn't make sense if she herself took her car. My sense is it's personal, and the timing isn't coincidental. Her returning from vacation is important, someone was stewing while she was gone and/or snapped once she was back. Within hours. My guess is she left that morning, and investigators know where she went or was headed. It follows that more information about the car is known. There's a waiting game on proof, but I'd bet a suspect has been identified. It could still be one of the workers who then enlisted the help of an unknowing drop off driver, but would she would have given one of them a ride out of the complex? I think a fuller scenario lies in unreleased camera/video from the complex. Two heads in a car isn't conclusive, but would narrow down when (and potentially to where) she left.