Perhaps I am misunderstanding your issues.
But if you select the node that represents the keystroke, you can disable the consuming of that event.
Also, if your actor is not attached to your controller, by default you will not funnel input to it.
Here is an example where I have implemented a simple Event Dispatcher titled TriggerWalkway
Pressing U in my scene all the blueprints associated execute.
Note the begin play where I enable input from a given controller.
