I think I would get boss' definition of "keeping an eye on things". Is it to make sure there isn't an injury/building emergency type of thing, or is it more of the "here is my whip and if somebody stops working you have my permission to use it" type? I think that everyone is interpereting it differently.
I think you should just go ahead and do your work, leave if need be, whatever. If PF starts to question you, the answer should be (in alightly distracted nature) "I have discussed (situation/illness) before with boss, but if you have concerns about it, I'll get with you and boss tomorrow. oh, by the way, do you have those documents for the beandip project?"
This is helpful twofold. 1: it brings to his attention (hopefully) that his own job is being neglected while he is micromanaging, which is something you can bring up to the two of them the next day; and 2: you don't have to be summoned to another room for him to bawl you out because you aren't trying to hide anything and are willing to go to boss WITH PF to clear up any misconceptions. Chances are, he isn't going to want to go in front of boss with you because of his own actions and the chance he will be found to be at fault. In essence you are calling his bluff, but in a polite non agressive way.