Who told you about this polar parrot fish ? It’s the first time I heard of this parrot and I can tell it’s bogus and Im guessing for fun: a piedbald parrot with white like the Midas(hypothesis)?
Because they are short doesnt mean they are parrot crossed. Its a chosen deformity.
When you cross a parrot with a cichlid, you get the random % genetics of Red devil and Synspilum. There Might be around 5% of getting short body out of that batch because of the deformity created in the fish’s bloodline already.