Maybe the original LK-99 sample was contaminated with actual high temperature superconducting impurities.
There is, a combination of strong (but not amazingly strong) diamagnetism at low field strengths and soft ferromagnetism (in floating samples) at high field strengths. Which is exactly what the paper in the link observed while getting the same results everyone else has. The only unambiguous sign of superconductivity was the original resistance graph which can apparently be explained by contact issues with four point probes (you can argue that they must have done many experiments and surely didn't cherrypick just the one where they found "superconductivity", but consider the quality of the rest of the paper...)
Doesn't diamagnetic levitation require a specific arrangement of the permamagnets that is not recreated in these videos?
That's not clear, but either way--as I've told you several times--there has been no credible demonstration of stationary levitation for even very weak uses of the word "credible."