we have known
there are 3 simple groups arising from $SO(8)$, i.e.$ SO(8,F_{q})$, $2D_4(q,q^2)$,$3D_4(q,q^3),$ so I want to know For the $3D_4(q,q^3),$, what is the corresponding Frobenius?
In fact, I know the non-split Frobenius map is the standard Frobenius followed by a graph automorphism

