One scenario that I can see that would think of that would get both girls to throw down bikes and a purse would involve a puppy and a predator. the predator simply releases the puppy and it runs to the girls who would pick it up and bring it back to the perp and both be grabbed and gone before you know it.
That hole in the fence bothers me. It's so close to the highway.
I definitely agree about a puppy. What a perfect lure for most kids!
I think you can rule out the highway. Right now, I-380 is under construction and both directions are squeezed onto one side, turning it into a two lane road with itsy-bitsy shoulders.
It's a designated truck route and, with the construction, traffic is basically bumper to bumper all day long. There really isn't anywhere to safely park a vehicle without causing serious amounts of disruption to traffic.
There are construction crews on the other side of the road and it always seems like there's at least one guy standing there, looking around while he waits for his turn at some mysterious construction chore.
It isn't so clear from the overhead views but the terrain between the shoulder and the 8 foot interstate fence drops steeply and is pretty deep in weeds.
I just don't think anyone could park a car and leave it, even if there were a driver in the car. It would probably stop traffic on that side of the road because the shoulders right now are partially taken up with making lanes. Semi trucks would be hard put to squeeze by a parked vehicle; the drop off means that a vehicle couldn't pull off the road entirely.
A better place to park a vehicle would be in the trees right by where the bikes were found. There's a sort of trail going back into the woods there from Arbutus Avenue. It is curved, so once a vehicle goes around the curve (and closer to the bike trail), it cannot be seen either from Arbutus Avenue or the bike trail.
I think you're right that a puppy would get many kids to stop and just let their bikes fall while they helped the owner by catching the puppy.
Ooooooooo, I just realised it would not be difficult at all to teach a puppy to run up to people on bicycles all waggy and happy looking. Just take a few afternoons beforehand (and in some other location) to station the puppy next to a bike route and have a bag of treats. Every time a bicyclist stops, ask them to "help socialise" the puppy by giving the pup a treat.
Most people are more than happy to help dog owners train their dogs, particularly if the dogs are toy sized or obviously puppies.
A couple 15 minute sessions like that and the puppy would most likely regard anyone on a bike as a potential cookie dispenser.