If the stud were smokey cream and heterozygous, there would be only one way to even tell, and that would be through testing.. his foal with the b&w mare wouldnt show smokey cream as a heterozygous form either.. the foal would look simply black..
As for the 'palomini' no, why? Because black is dominant over red.. 'ee' is red 'Ee' is black.. There is a forum of heterozygous arouti, 'a' but it wouldnt show as a bay horse. I agree with that.. but since the second foal with the buck mare isnt a perlino, it makes me think champagne.. it even has mottled skin on its muzzle, and amber eyes. 2 cream with agoutiwould be a perlino.. that horse is obviously amber cream.