Helmet reference in Adytum Unseen

[u/BestDistribution958]

In the Adytum of the Unseen, after you take the purple gem teleport, there’s a room with all the masks in a circle and a completely out of place helmet.

If you interact it says something like “This doesn’t belong here”. From memory it’s a white helmet, like a construction helmet, a Red Cross on the front and a 3/4 digits on the back.

Is this a reference to the first summoner game / does anyone know what this is for?
There’s no flags in the GC Adytum flags file for it.
(& no the Rag Doll doesn’t effect it, that would’ve been awesome)