Is ths easier to decipher?
Not a bit better, just longer. I get you want to obtain some kind of feedback measurement value to an arduino to (possibly) control additional pwm devices based on what a master one is running at? Perhaps a block diagram drawing would help us, and possibly instead of how you want to perform a given task, first explain what the final results are. There may be a much simpler way to have the same outcome then what you are imagining.
Lefty