I don’t know if that will help you, but usually when I need a “in-between zone” (because I have no idea how to get to those zones / to get them on the screen as a whole or whether that’s even possible) I just re-uplaod the background so that it fits my needs, which means I go to the Art Catalogue, go to Backgrounds, click on the background I want (in your case EXT. ST ANDREWS HIGH SCHOOL - DAY) and save it in the downloads of my laptop as a file with a right click. Then on the very left, on top of the page, right under all the Backgrounds, Animations, Overlay buttons it says “Available for All Stories”, if you click on it you can change it to “Uploaded to your account”. Here I just upload the background I just saved and choose always one panels less than what the original size of the background would be, in your case 2 panels instead of 3, and make sure that whatever I want to have in focus, in your case the door, is fully available in one panel. Then I upload it. The downside of this method is that backgrounds sometimes need quite some time to be approved, but you could eventually just skip this scene and keep on writing the rest and maybe come back to it later?
I’m sorry that I couldn’t really give you an answer on your question tho since I genuinely have no idea how to do something like this with just coding.