https://www.gamespot.com/articles/metal-gear-solid-seems-to-get-a-shoutout-in-ghost-/1100-6458170/

Ghost Recon Wildlands' new Special Operations I update is themed around Splinter Cell, effectively throwing a bone to fans of a series that hasn't been heard from since 2013. But it also seems to feature a brief reference to Metal Gear Solid.