
RumpinRufus |

If you can make them both shaken and sickened, then both effects stack.
However, if the idea is to use a cruel whip with the Enforcer feat, the shaken condition happens after a successful hit and a successful Intimidate check, so the creature is not shaken when you hit it and the cruel enchantment doesn't take effect.
If you can hit it twice in the same round, causing it to become shaken with the first hit and sickened with the second hit, then you can apply both conditions in one round.