Agree. I thought that was the original purpose of the AAAA, actually, so I was happy when I got it. But nope, it only works in those few Dead Hills HAs. Pretty disappointing.
It works in other expansions. It has to be max evolved for any raid event locks (e.g. RoS) and using the right reagent for the particular lock. The success rate is very low however.
The other reason they don't count and epic turn ins don't count is because the mobs have a different ID that the regular ones.
I carry 100 of each: Lesser Scrying Stone, Scrying Stone, Greater Scrying Stone. Activating my max evolved A5 will use one of them depending on the type/level of the locked object. It has to be an object you can target though. A door like that in Sebilis is not target-able so the A5 cannot work on it.