The cage would NOT be of adequate size for two adult amazons. These guys get pretty big with sizes of 5' commonly reached and two animals like that would be too much for the cage. The cage might be sufficient for 1 of the animals depending on how you would like it set up.
You also have the situation of feeding responses and when two animals are in the same cage and it's feeding time it can be pretty chaotic with both in such close proximity. My recommendation would be two cages or a much, much larger enclosure.