"RTH fly backwards for 50 m on its original flight route" straight flight or actual path?

[FafaZoli]

Here is the relevant section of the manual:
The aircraft will fly backwards for 50 m on its original flight route and ascend to the preset RTH altitude to enter Straight Line RTH.
The aircraft enters Straight Line RTH if the remote controller signal is restored during Failsafe RTH.

The second sentence explains why your drone did not fly 50 metres before entering straight line RTH.
The drone regained signal 10 seconds after signal was lost at 5:54.1 and on regaining signal, the drone entered straight line RTH.

We can't be sure.
If the hill had no trees or just small trees, the drone should have cleared it and the battery level was good for the return flight.
But if there were trees 50 ft or higher, that might be the problem.
But without data to show what happened after signal was lost, we can only guess.

Thanks for the explanation.
Yes, the connection was regained, but I could not do anything with the controller.
A remember that no video transmission, no control/gps tracking appeared on the mobile screen.
I could not take back the control.
Anyway I launched a ticket at DJI, and will use my flyaway coverage after they confirm what could happened.
I will keep you posted about the progress.