I have found that Litchi Pilot running on the DJI controller (RC Pro and RC Pro 2) does not correctly export to the DJI Fly KMZ format. I would prefer using your app to create, edit and then export missions.
In the meantime I am using Litchi Hub on Firefox on my controller to export to DLY Fly KMZ format. This works flawlessly. I thought I would mention it in case you were not aware it.