Ah yes - although the situation here is a bit different, as we talk 2 point-to-point connections.
But yes, Aegean covers it all by saying "no other airline on the ticket".
Disappointing
Maybe we should update the Wiki mentioning this point, e.g. under bullet 2: not only does it need to be Aegean or OA stock, but also all flights on the ticket need to be with those airlines.