Bullying at a previous affiliation, but now moved on. What to do?
Regardless of what labels are applied to the situation, it sounds like you left to get away from these people. Continuing to engage with them seems like it will undermine that plan and keep you involved (at least mentally) in a situation that's not doing you any good. I think I'd suggest at least contemplating the idea of cutting the cord.
There's no need to choose between taking revenge or forgiving and forgetting. The better option is to just accept that you no longer work with them, and that they're no longer a part of your life, and get back to living for youself. Trying to decide between revenge and forgiveness is (a) just your brain trying to keep you psychologically involved in a situation that ought to no longer concern you, and (b) a waste of valuable time in your new life.
TL;DR: In the kindest possible way, try not to let your brain get in the way of your new happiness, and move on.
p.s. To be specific, if they ask you to do any further reviews, a polite 'sorry, I don't have time right now' is more than enough.