This is why we have multiple confirmations and public databases:
The Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) was set up in 1996 with its headquarters in Vienna, Austria. It is an interim organization tasked with building up the verification regime of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) in preparation for the Treaty's entry into force, as well as promoting the Treaty's universality.
All six nuclear tests by North Korea were clearly detected by Australia’s IMS seismic stations,” Zerbo said.
~ https://www.ctbto.org/resources/for-the-media/press-releases...https://www.ga.gov.au/education/classroom-resources/hazards/...