First, you don't say whether it is acknowledged that your hearing loss is 'attributable' even though others suggest it is.
You say you have recently returned to flying. If your claim is successful, will that impact on your continued suitability to fly. In addition, what would be your status if later the service pulls the plug on your flying because of your hearing loss.
That said, you need to appeal the points you have made ie 'press to test'. You also need to ensure that you have access to an acknowledged 'big cheese' in the ear, nose and throat world.
Have you any HSW documentation or such like which says your working environment is unhealthy and have any measurements been taken which supports your case.
Old Duffer