Hello, and welcome to the forum. Thanks for posting pics of this helmet.
The silk portion type of liner can be found in Austrian shako's, even though I see it has a Bavarian maker on this liner. I've had a high-quality Austrian shako in the past, and it had this type of silk liner in it, with no access to any of the metal fittings coming into the shako, such as to the split pins or screw posts, etcetera.
I'm puzzled as to how the access would have been made through this type of liner to replace the back star on the spike crossbase (which is clearly different than the other two stars) + also change the odd-looking Bavarian kokarde to the wrong side of the helmet, and remove the national kokarde as well (if it ever would have had a National colors kokarde on it).
I agree that the liner is really "high-end/high-quality" as Joe mentions. I've simply never seen this type of liner in a pickelhaube before, only in Austrian shakos. Even the deluxe liners in several of the Kaiser's various headgear appear to have split silk liner access to the interior of the headgear, as shown in "Deutsche Offiziershelme aus der Kaiserzeit 1870-1918", Volume 2.
I simply have my questions as shown above, and am puzzled by these points, and am seeking answers to them, as you are also. Thanks again for posting pics of this helmet!
All the Best,
Alan