Another way of saying reinstate is he's got to 'reverse his decision'.
复职的另一种说法是reverse his decision（改变决定）。
It means Paul has got to make an awkward call to Denise.
Look Paul, you're going to have to call her and tell her you've made an error… a huge one actually.
It wasn't that huge?Actually… Anna, you're her good friend, would you like to call her?
Me? ! B-b-but I can't.What a coward!I think it's time to stand your ground Anna.
Tell him "You're the boss, I think it's better coming from you", and remind him "it was your decision so you need to explain the situation", and remind him "this is your responsibility".
You could suggest he says "I'm sorry, I made a mistake and we would love to have you back."OK.
Do you know what Paul, I think the news is better coming from you… just to make it official.
Yeah Paul, you are the boss after all.
And it was your decision in the first place so you need to explain that the situation has changed.