We ran into this issue as well. It isn’t mentioned anywhere but you’re going to want to include all of your maps in the “DefaultEditor.ini” file. Add the following code into your DefaultEditor and you’ll be good to go
[AlwaysCookMaps]
+Map=/Game/Maps/Map_Name_01
+Map=/Game/Maps/Map_Name_02
+Map=/Game/Maps/Map_Name_03
This solved the issue for us on iOS and Android builds.