LIBD, Bari, 26/07/12:
History | Weather Underground LGKO, Kos, 26/07/12:
History | Weather Underground
It's true there was fog in Kos which was limiting visibility to 4 km, but as far as I remember IFR flights do not have a minima for visibility.
I tend to agree with redsnail, weather may have been an excuse not to be liable towards customers. I would not be surprised of that since I experienced a similar situation with another LC vector.