if the fragment is legit and not the result of contamination it isn't "crushing" evidence that life on earth originated from other planets. It could simply be the case that, under the right conditions with the necessary elements etc, organic life can develop independently. The development of life could be much more common than previously thought.
good comment from the page:
"And if they are fossils from space, it does not prove panspermia happens - fossils are dead. And even if it did prove panspermia happens, it does not prove panspermia happened HERE. We may still have originated here, in that scenario; if abiogenesis happened once (necessary for panspermia), it can happen multiple times, and is as likely to have happened here as anywhere else. These wild claims really don't lend credibility to the scientist making them, or his analysis of the material in question."