I'm no legal expert but I dont think anyone is required to participate in a police investigation, even if you're able to. Obstruct it, no, but forcibly participate in it? Plllbttt. I can see VW doing damage control but I doubt they are in any real trouble.
I worked as a network analyst for a cellular company in the mid 90's and even with those early analog AMPS cellular systems, we could pinpoint with a reasonable certainty where a phone/car was located, within a certain radius. We would get people all-the-time calling, begging the people in the call center to tell them where a phone was, their car was stolen/daughter was kidnapped/theres a killer on the loose blah blah blah, you name the reason I heard it.
We had "police" calling in all.day.long, constantly, and they would end up on my desk. Sure I can tell you where that phone is pinging, drop off an order signed by a judge and I'll tell you whatever you want. Hey, we are THE POLICE! No, you're a voice on the other end of my phone and for all I know, you're a jealous ex trying to stalk your wife/husband and find out where they are, which is what 99% of these phone calls ended up being. In almost seven years you know many signed orders/subpoenas we actually got? Single digits.
I could track phone locations, and did when I had to or wanted to, but it ate up a lot of time watching the phone signal bounce from one cell tower to the next, and digging into the (crude by todays standards) data trying to see the signal db between the various antennas on a given tower/antenna sector, so we didnt do it unless there was a really good reason. And just because you're a cop doesnt mean you can call whoever, claim to be the police, demand whatever, and you're going to instantly get it.