Obviously you can't use your keys to open the safe that contains your keys, (unless you use some special Star Trek logic carefully applied to the problem).
By the same (non Star Trek) logic, you can't use an event generated by hook to do anything if hook is disabled. So it is impossible to use hook to turn hook on.
You could use some other event, or even a voice command to turn hook on.
You could enable and disable groups to control when the events were ignored, or used to trigger Vera scenes but this would not change whether hooked keys were blocked from going to MCE.