After taking a second look at all the flight data, it seems that the craft was just commanded to crash....
This is what happened at the end of the last flight with apparently normal ending :
View attachment 115174
The throttle stick was held all the way down when the craft was 0.6m above the ground ( wet sand ? ) so the craft entered forced landing mode. This is normal response but the craft was going forward at full speed at that moment becasue the full-forward elevator was applied. The flight data did not record it but landing at such speed can only result in crash.
Just 8 seconds after the end of the above-mentioned flight, the log registered another take off, home point recording and compass error before the craft rolled over and came to a rest. The whole "flight" last only for 3 seconds. I am convinced that this was not another actual flight but just a continuation of the previous one. The recording of a new flight must be due to some software glitches. It seems that the compass error message was caused by the crash.
Does this match what you saw ? If you can dig out the .DAT files, more insight can be obtained.