I need to upload own map data for Waypoint flights in remote areas

Good day
I am a new drone owner (Mavic2 Zoom) and new to this forum. Apologies in advance if I am repeating a subject question.
We own and run and guest farm located in mountainous area of the Western Cape in South Africa. We have recently developed new hiking & trail running trails on the farm and would love to add video footage of the trails on our website. My intent is to use the Waypoint flight functionality to fly and record the wanted footage.
It goes without saying that our farm is not mapped, and the satellite imagery available in the DJI Go4 Pro app for the area is hopelessly outdated to.
I have detailed GPS tracks and coordinates available from our own mapping of the trails (stored and used in Google Earth).
Is there any way that I can use and/or upload the GPS data from Google earth to augment the maps displayed (cached version?) on the DJI Go4 Pro app and/or building and storing flight paths for the Waypoints functionality?
Thank you in advance for any input.