Korean scientists announce room-temperature superconductor. Ridiculous amounts of squabbling over who invented it immediately ensue, even though the jury's still out on whether it even works.

https://en.wikipedia.org/wiki/LK-99

The part I don't understand is why they don't just FedEx a sample of the stuff to another lab, so they could replicate the results immediately.

Bc that's not how independent scientific verification works. Other labs need to replicate it themselves to avoid/reduce any bias from the original experiment.

Some Korean researchers have released a couple half-baked papers apparently due to some infighting and a Nobel prize grab?

Their claim is for an easily/cheaply synthesized room temperature ambient pressure superconductor. They call it LK-99.