After several iterations, I managed to salvage this tricky subject as best I could.
Recorded with an Insta360 X5 at 4 elevations. Exported at 4 fps in a failed attempt to try to accurately capture the intricate reflections of the surfaces. The up-and-down motion I used at the end of the recordings caused misaligned images, so I removed those from the training set, they included few novel poses anyway.
LoMa feature extractor, no rig during pose estimation.
The surroundings are trained with fisheye images, the heart combines the splats of both a fisheye and a cubemap training.
Subject: "Het Blauwe Hart" by Marcel Smink - 1998. Capture quality 6/10.
Surroundings: Small square besides the New Church of Delft - 1496 (Europeans have a funny interpretation of the word "new"). Capture quality 9/10.