i notice this same no gps info in exiftool and in srt file :( other DJI drones store position in srt file if you change to mp4 file format but no MA :(
i have too all these same problems and all stop after today i hard reset my phone samsung J7 and install DJI GO app again ! Make 2 test flight and no problems like before ! i hoppe this is end of my problem with MA and FW400 !