I) The Hamilton-Jacobi equation (HJE) itself sure ain't enough as an axiom without some kind of context, setting, definitions and identifications of various variables.
II) Let us assume:
that Hamilton's principal function $S(q,P,t)$ depends on the old positions $q^i$ and the new momenta $P_j$ and time $t$,
the HJE itself,
the definition of old momenta $p_i:=\frac{\partial S}{\partial q^i},$
the definition of new positions $Q^i:=\frac{\partial S}{\partial P_i}$,
that the new phase space variables $(Q^i,P_j)$ are all constants of motion (COM).
III) Then it is a straightforward exercise to derive Hamilton's equations for the old phase space variables $(q^i,p_j)$ provided pertinent rank-conditions are satisfied for the Hessian of $S$. [This result is expected, because (5) is precisely Kamilton's equations and the function $S$ in (1)-(4) is a type-2 generating function of a canonical transformation (CT).]
IV) The Lagrange equations follow next from a Legendre transformation. In turn, the Lagrange equations are Euler-Lagrange (EL) equations from the stationary action principle for $\int \! dt ~L$.