What I see is, that I could not find any GCP’s at all, just 3 markers on the ground, but in your list there are more rows than markers. So it is really hard to process the dataset and tell you what’s wrong.
If you are on budget, try making these: DIY Ground Control Points - Learning Area - OpenDroneMap Community (Also forum mods: could you please open that topic, I would like to add some more information)
If not, do you recall if you adjusted --gps-accuracy any? What is your expected average GPS accuracy for the entire dataset? We currently have that flag default to 10m, so if your data are more accurate than that, you might get an improvement by constraining it to something closer to your mean GPS accuracy.