Yes he's chestnut tobiano, and no, in order to throw a palomino at least one parent must carry cream. One copy of cream on chestnut gives you palomino,one copy on bay gives you buckskin, one copy on black gives you smoky black.
Two copies of cream on chestnut gives you cremello, two on bay gives perlino, two on black gives smoky cream.
Since neither stallion nor mares carry cream, she'll never get a palomino from those crosses.
She'll never get a palomino from that stallion unless she puts him on a mare with cream, and even then it'll be the mare not the stallion that's thrown a foal with cream.
Two copies of cream on chestnut gives you cremello, two on bay gives perlino, two on black gives smoky cream.
Since neither stallion nor mares carry cream, she'll never get a palomino from those crosses.
She'll never get a palomino from that stallion unless she puts him on a mare with cream, and even then it'll be the mare not the stallion that's thrown a foal with cream.