Hello all, thanks for your comments.
While we believe the real solution would be a local adjustment to a known datum on the map, something we expect to be working on in Q2, we are going to enable a feature toggle to use the AMSL estimate that the GPS on DJI drones provides. In combination with the barometer on the device, we think this may at least be a good start for you.
We can then incrementally add the ability to provide an offset / datum on top.
@JimBob - would you be willing to test this out on your account if we can enable it in the next few weeks?