Hello Ollie,
maybe, it would be useful for the future projects. I tried to make a similar hw configuration without success. If you are working with CAN, it is clear how to use standard and extended identification. But, the trouble is, how to use proper bit mask. At first, your device is sending id: 435294464. Binary that means: 11001111100100001000100000000. It should be 29 bits, i hope. But the extended id is described by 30th bit. It should by 1 for extended ID. The structure of extID consist of 32 bits. Thus, originally your message is defined by 19F21100, but the input of CAN recive ID should be 11111001111100100001000100000000 or F9F21100 in hex.
Regards
Jiri