Epimorphism that is Split Monomorphism is Split Epimorphism
Theorem
Let $\mathbf C$ be a metacategory.
Let $f: C \to D$ be a epimorphism and a split monomorphism.
Then $f: C \to D$ is a split epimorphism.
Proof
Dual proof of Monomorphism that is Split Epimorphism is Split Monomorphism.
$\blacksquare$