I'll try to analyse this
Grandma:
Mum shows Crystal Crush
Dad shows Dry Olive
Kitten shows Ex Breeze which is known to be dominant to Dry Olive, and must be Jo Jo's hidden eye.
Dad:
Mum Shows Cognac and hides Ex Breeze from grandma
Dad shows OCM and may hide Cognac.
Kitten shows Cognac from mum or dad
Mum:
Mum Shows Galaxy Moon and hides Ody Bellini or more recessive
Dad shows Jade and hides Jade or more recessive
Kitten shows Jade, which is known to be recessive to Galaxy Moon, and hides Mum's hidden eye
Offspring:
Mum Shows Jade and hides Ody Bellini or more recessive
Dad shows Cognac and hides
either
Ody Cognac Moon or more recessive from grandpa
or
Cognac or Exotic breeze from grandma
Kitten shows Ody Bellini which is Mum's hidden, and hides Ody Bellini or more recessive from Dad
This means that Dad's Cognac
may be grandpa's hidden eye
and that his hidden is Exotoc Breeze from his mum.
If grandpa's hidden eye can be proved to be dominant to Ody Bellini, we will have proof that Cognac is recessive to Ody Cognac Moon, and Cognac will be placed between OCM and Twilight.
A much easier way to prove this will be to breed Grandpa Pippin to a female showing a recessive eye to pull his hidden.