Questions - Resort Shirakami winter

Hi all,

Planning to stay at Akita for a couple days in January 2024 and have a few questions about the Resort Shirakami train.

1) Is JR Pass valid on the train?
I've searched the JR East website but there is no mention of this. I think the answer is yes because JR East is part of JR? But if someone can clarify/confirm, that will be much appreciated

2) How to book the seats?
We'll arrive in Japan (Nagoya) around 23 Dec and wondering if it is possible book the seats at the JR office in Nagoya when we activate the JR pass? (planned trip for Resort Shirakami is 11 Jan 2024)

3) Hirosaki or Aomori?
Our plan is to take Resort Shirakami from Akita to Hirosaki/Aomori one-way then take a standard (faster) train back to Akita. Just wondering if you have 5-6 hours to spend in either Aomori and Hirosaki, which one would you go for? And if any suggestions on what to do or eat, that will be great.

Thank you in advance :)

1) Is JR Pass valid on the train?
Yes.

2) if it is possible book the seats at the JR office in Nagoya
Yes

3) Hirosaki or Aomori?
Either, but the train ride uses much of the day. Hirosaki has its castle and castle park. Aomori has the nebuta museum and a couple of other things around the station area.