Had contacted Codemasters about the issue and the only response is a sorry. The disc being for US region , the DLC has to be purchased on an PSN account thats connected to US store / geography .
Now this is ridiculous since the PSN store lets you purchase DLC's and there is no way to check game compatability at that time . There is no notification or warning shown even
Given that customers pay for the DLC's and end up not having a way to use it ( or return it ) its a huge waste of money and time. Codemasters should take this seriously to make sure DLC's work across all game disc's