From my research on this subject, I was convinced that Nissan does not formulate their own oil products and that Nissan simply uses a oil that meets their specifications. My findings follow -
Nissan-matic j fluid is a semi-synthetic JASO 1A spec ATF actually made by Castrol and sold to Nissan relabeled and sold for 3-4 times the cost.
Castrol Transmax J, which Castro made to work in all JASO 1A spec Japanese, is available at most auto-parts stores.
I followed the Infiniti shop manual instructions for changing the transmission fluid in my 2007 QX56. Eight quarts and thirty minutes later I was satisfied that the fluid had been freshened up to Infiniti's specifications.
10k miles later the transmission shifts in a climate ranging from 0 to 100 degrees like the day I bought it.