Hmm that is an interesting bass.... that certainly isn't a standard looking neck construction to me and the fact it seems to be non laminated and with a join leads me to wonder if if could it possibly be an early prototype or test bass or maybe a replacement neck or headstock. It certainly needs to be verified before parting with money.
Alembic are critical with detail so even small things like the logo and the brand name not being centralised on the headstock gives me concern.
Do you have any chance to check out the bass in person?
Certainly ask the seller for some pictures of the control cavity and the truss rod cavity to see if the electronics are standard and it has a dual truss rod neck.
Some other things to note.
Also note there is a serial number stamped on the back of the headstock on this picture of an epic bass, something I don't see on your photograph.

Here is a clearer view of a typical Epic neck construction which again seems different in your pictures.

Also note the position of the alembic name tag appears under the D string tuner not above as in your picture.

Others with more keener eyes and knowledge of the Epic model may offer a different or supportive analysis of what your pictures show.