There's a fundamental problem with the Unix timestamps. It looks like you started with a good value, but then made an error in calculating subsequent time stamps.
Your start time is Wednesday, November 7, 2018 3:19:00 PM
and Your end time (2735203940000000) is Sunday, September 3, 2056 10:52:20 AM
So the multiplexer is expecting a video file of ~38 years duration.
Check values at https://www.epochconverter.com/
I would also recommend that you do some averaging to filter out bad values, e.g. your Sensor Relative Elevation Angle shows changes from -49 degrees to zero and back to -49 degrees between 3 records. I'd apply a moving average (e.g. perhaps a weighted average of 5 records) if you can't get more reliable data from your orientation sensors.
Although the multiplexer can sample a DEM to calculate footprint, note if your Sensor Relative Elevation Angle suddenly reports the sensor is aiming toward the horizon (0 degrees), the software will attempt to sample the DEM in the direction the sensor is looking - and a radical orientation change of 50 degrees from one record to the next (even if that is NOT incorrect!) will increase processing time and is unlikely to give you good results. I'm assuming those values are not correct, so if you smooth out the values you may get better results.
Last, the Sensor Relative Azimuth Angle is intended to be 'in addition to' the Platform Heading Angle - so if the drone is flying north, Heading is near zero, but if you have a gimbal pointing east, your Relative Azimuth Angle would be +/-90 (sorry I don't recall sign +/- off top of my head; not double checking that detail right now). If you don't have a gimbal that can aim the camera independently of the drone, your Relative Azimuth Angle should be zero. If (for some reason) you had a camera fixed at some angle left or right of "forward", you'd have a fixed value for Relative Azimuth Angle, and the drone heading would give the Platform Heading Angle.
Try the attached file, and instead of using the DEM, just enter a fixed ground elevation of 307.5 m. Since your drone did not move very far horizontally, this should (might) give you reasonable results.
Note this does not explain "ERROR 002652: Unable to parse the header of the metadata file" but I'll try to test further.
Cody B.
