I think you need to have a full and frank discussion with GECAT. Part of the contract you signed up to was that you and your buddy paid x amount to get y in return. By doubling up it gave GECAT a degree of economies of scale in running the course and ensured a hansom profit in return. If he is not playing ball then it isn't your issue but GECATs to sort out. Afterall it is the TRTOs that make the rules that require you to be partnered up with someone who you have presumably never met before.