Do you have the devkit to reproduce the same issue?
We’ve verified the loopback test as yours sending data from CAN0 and received at CAN1 working on AGX Orin devkit+R35.5.0.
Could you also share the block diagram of your connection?
It seems you enter in to bus-off state. Is there any chance that CAN-H/CAN-L shorted in your case?
Please refer to the following thread to apply the change and check if it could help.
Jetson AGX orin can0 - #7 by KevinFFF