No ID for some achievements in the API ?

ReActif.9251

I'm looking for the ID in the API for the achievement of Season 5 Episode 1: "Legendary Bonerskinner" & "Legendary High Shaman".

The strangest thing is that the game has to record this somewhere, and it normally does it for Legendary Voice and Claw with their ID well identified but absolutely not for the Boneskinner and High Shaman.

Does anyone have an answer or the IDs in question?

For ref : Legendary Voice of the Fallen and Claw of the Fallen = ID 5023

I really did a search with all the API updated locally and with all the terms even truncated and I even searched the API in another language.

ReActif.9251

Same problem for anothers achievements (i'll list here if i find anothers)

Season 5 - EP 1 - Whisper in the Dark :

• Legendary Boneskinner
• Legendary High Shaman

Season 5 - Visions of the Past :

• Fallen from the Summit
• Visions of the Past: Lair Light-Foot

ReActif.9251

I search in this API : https://api.guildwars2.com/v2/achievements

ReActif.9251

After talking to a more knowledgeable player, this could be related for some players to a rotation and thus an absence of IDs during the weeks they are not there.
And for others it could come from the fact that I query the API and have the cookie that identifies me and I didn't make that hit and therefore prevents me from having it, I guess at least.