The NSA does not need to "request" time to use an n-day vuln. They have more 0-days than you can imagine.

They literally employ full-time Vulnerability Researchers doing nothing but 0-day discovery and PoC creation 24/7 to add to their horde. Plus contracting with the MIC for their full-time VRs for the occasional project.

Exactly. Something like this is often the NSA realizing one of their pet vulns is being exploited in the wild by someone “not them” and so they burn it.