Victorian thought is not dead I see.

Well, instead you might incentiveise it through having car pool car parks that are closer to campus, or at least next to a well lit and preferably sheltered area. Then you could publicise the car pool scheme. You could even have a forum for finding other car poopers, and/or an app. Maybe allow people, with their consent, to be matched by approx origin/destination for easier finding.

If you had a computer science or math department then I'm sure they would have people who could solve the ride matching problem.