You may already know, but let me share some information here.
1. 95% of red pandas in Japan zoos are Sichuan-Chinese red pandas.
2. Atagawa Tropical & Alligator Garden (aka Bananawani-en zoo) is the only place in Japan where 10 Napal-Himalayan red pandas are kept. Most of them are same family, so there's not much chance of breeding Himalayan red pandas in Japan from now on.
3. Domestic matching/breeding/transferring is managed by Nihondaira zoo. Any zoo cannot freely breed red pandas.
4. In recent years, Japan zoo has become overpopulated by Sichuan red pandas. More than 10 red panda cubs were born every year. Some of them are relatives, and some of the zoos have no more room to keep them.
5. From the last 2 years, I heard from a zookeeper that Nihondaira decided to slowdown the red panda breeding plan. Last year, there were only 2 cubs born and alive in Japan. Ako (female) from Kumamoto zoo and Emi (female) from Nihondaira zoo. Actually, more than 2 were born, unfortunately, they suddenly passed away.
6. This year, there are still only 2 cubs born. One from Hamura zoo and one from Hiroshima Asa zoo.
7. It's obvious that Japan wants to balance the red panda population by temporarily reducing the birth rate and transferring them to other countries.
8. I haven't heard about the future plan yet.
There is a male from Taipei Zoo, Croissant (aka Kason, Keson). His parents both were from a zoo in China, so this lineage is quite rare and precious to Japan.