Read-only map review: no proposed source patch is approved or applied.
The scratch DiscoveryMap.c override was abandoned after SDK review; do not integrate it.

Concrete compatibility boundary:
/tmp/erri-vanilla-stock/scripts/Game/Map/Markers/SCR_MapMarkerManagerComponent.c:646-664 checks UGC privilege/restrictions for every static and disabled marker on map open. There is no exemption for local, owner=-1 or server marker. Lines417-444 hide blocked entries.
Current ERR_DiscoveryMarker uses this registry, so authored discovered sites/mine warnings are subject to that native filter. No restricted-platform native test was run.
Vanilla tasks use a separate SCR_TaskMapUIComponent : SCR_MapUIElement in scripts/Game/UI/Tasks/SCR_TaskMapUIComponent.c:1,46,109-116. It reads TaskSystem.GetTaskLocation and is not a static marker list entry. An objective-map-element migration is the supported architecture to investigate; changing platform filtering is not recommended.

Content origins checked:
SiteService configures Location.Label from authored SiteDefinition.Label; TerrainSites supplies fixed labels; DiscoveryMap chooses fixed rough/default strings or that authored Label/Id. MineIntel uses a constant historical warning. No current player name/chat input reaches these marker text calls. Third-party scenario definitions can provide authored labels.

Two focused programs passed current target:
- test_shared_map_ownership.py: actual owned map/config/root callbacks and cleanup.
- test_discovery_map_position.py: actual stable rough coordinates versus exact discovered points.
Native reopen/JIP and restricted-platform presentation are not qualified by these checks.
No target/native/UI/commit actions performed.