The iron and acidifier was probably a good idea... but it will take more than a couple of days to show any signs of helping.
The leaves probably won't go back to green... but the new leaves will look better. Which, since the tree is also going dormant, you may not see until next year.
Watch that you don't water too much. Let it dry slightly in between.
Other people with much more experience may also chime in here, and if so, their information is probably more pertinent. But my
guess is that the tree is mostly just going dormant, along with perhaps lack of iron.
Joanie