[open]GetCollectibleBlockReason(id) returns "not blocked" on mounts in dungeon
 

The API function GetCollectibleBlockReason(collectibelId) will return "not blocked" (0 -> COLLECTIBLE_USAGE_BLOCK_REASON_NOT_BLOCKED) if you are using it inside a dungeon or delve with the collectibelId of a mount.

But it should return
or
if you are alive.