Luggage Forwarding Kamikochi?

I am staying in a cabin at Konashidaira Campground in Kamikochi in mid/late June. I see that some hotels in Kamikochi offer luggage forwarding, but I can't find any info about whether the campground offers this. Does anyone know if the campground offers this service? Or is there a central spot in "town" (I know it's not a town) that you can forward your bags to and from?

(I am coming through the Kiso Valley to Kamikochi, with a stop for a night in Magome. So the other option is to forward bags from Kyoto to our next stop in Tokyo, but that will mean 4 nights without bags, which is a lot to pack into a daypack.)

https://ameblo-jp.translate.goog/paigaji/entry-12793193783.html?_x_tr_...

Originally in Japanese.

This guy sent 60L bag from Shikoku to Kamikochi Post Office.

"As a slob, I wanted to keep my luggage as light as possible, so I thought about a lot of things. I decided to go empty-handed, so I packed my sleeping bag, mat, cooker, table, and chairs into a backpack and took them to the post office.
I put it in a 60L backpack. Although it was a little heavy, I sent it as a small package to Kamikochi Post Office. Shipping costs also depend on the size, so shipping from Shikoku was \1,680 at the time."

As far as I searched this is the only option to send your luggage to Kamikochi.

https://www.kamikochi.or.jp/enjoy/public_facilities/2418/

Thanks! I have searched high and low for an answer to this. We may have to go 4 nights without luggage and just ship it to our next stop.