In Germany, only the driver can get fined, not the car owner. However, if the latter cannot tell the authorities who was driving their car at the relevant point

In Germany, only the driver can get fined, not the car owner. However, if the latter cannot tell the authorities who was driving their car at the relevant point in time, they can be forced to start keeping a written log of who's driving their car at any point in time. That's only for the future though, it does not apply retroactively.