Go to the OpenableWindow and create a new variable and set it like the image below. Make sure you set Replication to Replicated.
Next copy the images below by adding the highlighted nodes, location at the top of the screenshots.
Next go to the OpenableDoor blueprint and create 2 new variables and set them like the 2 images below. Make sure you set Replication to Replicated.
Then copy the images below adding the new highlighted nodes to your code, locations at the tops of the screenshots.