Here are links for the actual paper(s):
https://arxiv.org/ftp/arxiv/papers/2307/2307.12037.pdf
https://arxiv.org/ftp/arxiv/papers/2307/2307.12008.pdf
They do show super conducting property at room temperature indeed, the critical current is around 250mA though.
The first paper as well is not convincing at all.
Levitation over a (super-) strong magnet does not proof SC properties, that could be some diamagnetic stuff as well.
You need a proper sample with 4W connection, defined geometry, to perform electrical measurements to prove SC properties.
No picture, and no such information given.
For the Meissner effect on a bulk sample, you need its geometry to normalize the signal.
Using 2 phase AC susceptibility, the real phase χ' represents the magnetization of the sample, the imaginary part χ'' represents the losses, which go to zero if the sample is really super conducting. Therefore, the susceptibility is as well a measure for the electrical conductivity.
The resistivity of ordinary metals like Copper and Lead goes down for decreasing temperatures, (arbitrary units used), as can be seen in χ'. χ'' first goes up, but in case of Lead, which becomes superconducting at about 7.2K, the losses vanish at its jump temperature.
For an YBCO film sample, it's equivalent.
As both these methods for proving SC are quite old, and were intensively used on the then new High T
c SC, about 35 years ago, it is quite mediocre, what those guys have presented here, from an experimental point of view.
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Frank