I think you’re on something. The dodecahedron with its various size holes could be a gauge of you know, your equipment.
Best theory I’ve seen is that it is used in building, as a surveyors tool for making measurement over distance.
There’s a YT about using it for building camps, roads and the like.
Perhaps it could be used as a Go / No-Go gauge for coins?
Or an armorer’s tool for attaching a spear shaft and head?