Using Packet Sender om my laptop, I mimicked the Goodwe to see if I can get the UDP connection to work but the IP address provided seemed wrong. This may have something to do with the way our network is set up.
So as an alternative I pulled out a wemos board, found some UDP code and added my MQTT code. The wemos successfully requests the data from the Goodwe and passes it on to OH via MQTT. It’s a bit of a workaround but it works!