Panorama images generate chaos

I tried using panorama images (of an exhibition [so inside room] taken with my DJI OSMO 360) twice today, but the results are totally useless. Here are the links:

https://studio.aholo3d.com/3dgs-model/classic-gallery-art-exhibition-3FO4K4UR1UE4

https://studio.aholo3d.com/3dgs-model/heritage-hall-contemporary-art-exhibition-3FO4K4UR2236

One had 10 images, the other 38, all in their original size of some 15000×7000px. Any idea what I could have done wrong, or what I should do better?