It really isn't that difficult. SK does not pay for CPH Express nor does SK give access non-EB *G to their own Fast Track, this is why it flops. Award tickets are completely irrelevant. I highly doubt Aegean (or UA when they served CPH) pays for Fast Track at an outstation for their elites not traveling on their metal. Lufthansa's contract covers J pax, SEN, HON and all other *G traveling on LH and most likely OS and LX. It all comes down to which elites an airline decides to add to their contract and pay for it, so OP as TK*G on LH got access under published policy. It worked exactly as designed.