Listen only CAN scripting interface

I have an interesting scenario where I am using a device occupying one of the autopilots two CAN busses (not droneCAN sadly). There are some additional telemetry messages not natively supported by ardupilot that I would like to log via scripting, preferably without losing the second can bus. I see there’s an option to pass the PROTOCOL2 to scripting, but haven’t had any luck as it seems that’s only available on a droneCAN bus.

Is there any other way of having scripting listen only to an in use can bus? Other than a separate autopilot just to translate the data through a UART or similar