I don't know if this editor can replace the Reveal scroll; the editor for the Classic release could not (it could add a copy, but it wouldn't work to reveal the entrance).
Did you check the homestead chests, etc? There is a pouch container that has the same icon as a pouch of bonedust or moondust.
Did you check older saves, if available, until you found the most recent one with the spell, and oldest without? Knowing when it went missing could help determine what happened to it (dropped when organizing inventory, etc).
If there are a limited number of places where you may have been sorting your inventory, checking there with the Alt key pressed could help find it (or with Show World Tooltips toggled on using a controller).
If you can not find the scroll, please email supportdos@larian.com with your latest save. Each save is a folder in the '..\Documents\Larian Studios\Divinity Original Sin Enhanced Edition\PlayerProfiles\<ProfileName>\Savegames_patch' folder.
In Windows Explorer you can zip a file or folder by right clicking on it (or them) and selecting 'Send To | Compressed (zipped) Folder'.
