Thank you for the feedback.
The disabled E action is by design, actually. My intention was to require objects to be within the camera's view in order for the player to be able to interact with them.
If they could be interacted with off-screen, then a player who has played before will go through the levels without ever needing to make use of the camera.
Do you know if there's a better way I could have solved that problem? I'm always open to feedback.