You make an interesting point...I am curious if anyone did come forward and that information was never released because I don't remember. I just remember the huge DNA sweep. I believe that the person in the white car was involved, and for this to go down as quick as it did, there may have been more than one person. Regardless, as someone else said it was luck...sadly.
I think there are probably a lot of things we do not know about this case. I do not know if it was more than one person, but it will remain possible.
I prefer to focus on what we see out there on the beach. In the "Unresolved" episode, the detective working the case said Molly Bish got out of her mother's car, went to the shed, and was never seen again. I think this confirms she did indeed visit the shed on the property before she was abducted. I think the shed might be a small light green looking portable building that was in the parking lot right before you go past the gate to walk to the beach. This is a guess. I do not know for sure where this "shed" was on the Commins Pond beach property. What did she get out of the shed is a question I would want to know.
What was so interesting to me was all the stuff Molly Bish must have had in her hands when she stepped out onto the beach to set up that day if she only went directly to the beach after visiting the shed directly after she got out of the car. I think now we can probably also conclude that after she bought the water at the gas station she put the bottle in her bookbag. The reason is her hands had to be full.
I tried re-creating the crime scene by having that much stuff in my hands. The only real conclusion I came to was that you would have to drop everything in order to unfold the beach lawn chair. It seems awkward to try to unfold it with all that stuff in your hands. I think you would need both hands. But maybe that particular one you can unfold with one hand?
This is the scenario I have: Molly Bish arrives with her bookbag over her shoulder with the water bottle inside. She goes to the shed and grabs the first aid kit and beach chair. Is this what she got out of the shed? I don't know. All I know is that it was on the beach. She walks to the beach and puts down the chair, then the lifeguard kit, and then takes her bookbag over to the bench. I think maybe she wanted to keep sand off her bookbag by putting it on the bench. The witness who arrived at 10:20am said the bookbag was on the bench even though in photos is looks like it is under the bench on the ground.
She sets up the beach chair and first aid kit. Then she returns to the bench to grab the towel and water bottle. Again, I ran into a problem as I could not figure out how to put the towel over the lawn beach chair without putting down the water bottle on the ground or on the lifeguard kit. I thought maybe she might not want to get sand on the water bottle or sand sticking to it with the condensation. I think it was 80 degrees by the time she arrived that day at the beach. Maybe Molly Bish first grabbed the towel to put over the beach chair. Then she made another return trip to the bookbag to grab the water bottle.
After this I can only guess she stood around the beach chair drinking out of the water bottle. At some point, maybe as she was about to sit down to relax, she took off her sandals and put the water bottle in the right sandal. She must have put the water bottle in the sandal or else there would be fingerprints if someone else did. Then someone approached her faking an injury and she opened the first aid kit. This person abducted her before she was able to close the first aid kit.
The conclusion is she was abducted before she had time to put on her lifeguard whistle, make the daily two-way radio call in to the police department, or remove her outer clothing. All that remained in the bookbag.
It appears to me this person watched her set this lifeguard stuff up for at least a minute or two before approaching her. My guess is maybe they could hear the beeping from the backing up of the sand truck(if it had one of those beepers) or they could hear the truck's engine and wanted to make sure it was gone before they approached Molly Bish to try to abduct her. Or they just watched her for some reason.
The problem is when you do not know information that is true and correct and confirmed, all you can do is make guesses. I do not know if I have any more guesses to make with this case.