When my father was S2 with 1/12 (USMC arty battalion) he got a Navy com with V for defending a perimeter during an attack from the VC/NVA which threatened to overrun the compound, then led a subsequent patrol which killed some VC. Word was he was downgraded from a BS but I never could confirm that. I still have the citation around somewhere.
If he was downgraded from a BS he probably earned a BS/V. The Corps was adept at downgrading awards...in other words, "stingy".