I think the article covers that exact question (excerpt below)
Sakura Samurai coordinated with the U.S. DoD Vulnerability Disclosure Program (VDP) to assist in facilitating initial conversations of disclosure. John Jackson spoke with DC3’s Program Manager via email and coordinated on a plan of action
&
Roughly 4 days later, after further communication with the DC3, we felt safe to begin our initial reveal of research on the NCIIPC’s RVDP program.
Sakura Samurai coordinated with the U.S. DoD Vulnerability Disclosure Program (VDP) to assist in facilitating initial conversations of disclosure. John Jackson spoke with DC3’s Program Manager via email and coordinated on a plan of action
&
Roughly 4 days later, after further communication with the DC3, we felt safe to begin our initial reveal of research on the NCIIPC’s RVDP program.