Just if others find their way here.
I used the same link https://www.thomas-wedemeyer.de/beaglebone-canbus-python.html
Followed it all the way through for auto start etc and it works fine.
for candump you may need to install can-utils ........
sudo apt-get install can-utils
then cd /usr/bin
then you can just run
NOTE it is can1 NOT can0 !!!!
In codesys make sure to set the Canbus Network to 1 (Not 0) and the correct baudrate
Then add Canopen Manager and then a device.
And if the device is sending PDO's you'll be able to monitor this immediately.
Hope this helps