Guard Duke grants using public capture uncertainty

docs/DUKE_VIDAL_RULES.md

@@ -17,7 +17,10 @@ admitted Advanced Harkonnen profiles, the Ambassador acquisition descriptor
 uses actual Duke custody and may distinguish a secretly captured Duke from a
 publicly equivalent free Duke. Plain Advanced Ecaz/Harkonnen acquisition stays
 guarded until a public-safe solution is implemented. Broader capture assurance
-and deployed verification remain open.
+and deployed verification remain open. The later [public capture uncertainty
+policy](ECAZ_DUKE_ACQUISITION.md#public-capture-uncertainty--29-october-2026)
+guards the Ambassador availability issue described above, with explicit
+legacy and post-capture limitations.
 
 ## Occupied Ecaz grant — 26 October 2026