Is there a Abus wheel lock aka frame lock or cafe lock that would fit on radrunner? (One sold at https://radpowerbikes.pxf.io/Wq1EzZ doesn't seem to fit radrunner?)
As far as I know, the Rad City is the only model the ABUS Cafe lock and chain works with. Maybe Rad will add it for additional models. I think the Rad Mission would be a perfect fit.
You can consider Abus lock (https://www.bikeshepherd.org/best-cafe-bike-locks/). This cafe bike lock is convenient to use because it does not need a pole or rack while attaching your bike permanently. Also, locking in itself means it will stop the rear wheel from turning, which means it will be impossible for the theft to jump on your bike and steal it away from you.