Also it's a accuracy issue within dji go4. They only allow a margin of inaccurate of 10ft. If you download a gps accuracy app, both devices have never gotten better than 15ft accuracy. So the dji go 4 thinks that's not accurate enough. All dji has to do in next firmware update is to change ios operating systems to allow a inaccuracy of 16ft and it will solve everyone's problems. Although I know my phone is about 5ft accurate, it's just reporting to the app that it's 16 or 5m. Hope that helps.
I believe you have found the correct answer!!!
Several other sources have confirmed that the inability to set the Home Point to the RC location is a software bug on the Go App. This can only be corrected by DJI with an app or firmware update.
Unfortunately there's nothing a user can do to get around this. I will post a request they fix it on DJI'a own forum.
Thanks to all the others who offered suggestions.