I honestly don't know the difference between the Mopar ASRC ATF versus what Amzoil ATF is offering, but I do know that Amzoil tends to have a much more robust additive package than any other oil manufacturer, which is why they advertise being able to go further than more oils (they have more additive to sacrifice).
There are those that love Amzoil and those that are wary of it. All I can say on the subject is that Mopar has their recommended fluid and I don't believe they stated that the Amzoil stuff meets their specs. Kinda like the ATF +4 issue with the 68RFE. There are a few vendors that actually meet the spec and sell their product as ATF +4 (like Valvoline), and there are those that merely state that their product is equivalent to ATF +4. Another thought is to see if Aisin has any recommendations for transmission fluid for their AS69RC. I've personally never looked it up, but I know HD transmission makers usually spec some products, like Voith having a list of approved fluids, or Allison preferring Transynd but having another spec that is fairly common and easy to procure.