While I think it's possible that every piece of advice that's been offered up thus far could work, to me, this is always something that is hyper specific to each individual player and case.
I do agree that slumps are mostly mental. Well, I think they start with some bad luck (defense making good plays, etc) or whatever, but are sustained due to the mental piece. For some, its a horrible decision to hit the pause button. For others, it might be the perfect remedy.
My 2021 is typically apprehensive to the mental piece due to its "squishiness." He absolutely prefers to muscle his way through just about everything in life. Give him the option of spending 6 hours in the gym versus 15 minutes of critical thinking, self reflection, etc and he'll be in the gym before you finish saying the 2nd option. But I've yet to see him once muscle his way out of any slump. And its not for any lack of trying; believe me.
Honestly - to answer the original question - hitting pause and trying to go brain dead at the plate (for lack of a better way of putting it) may be just what the doctor ordered. if he's like most players (who have parents visiting HSBBW), taking a week off won't be nearly enough to set him back at all. One week - for kids who have played ball for what seems like 350 days a year since age 4 - is nothing. For most, distance makes the heart grow fonder. For all you know, "grounding" him from baseball for a week might give him a moment to miss the game in a way he hasn't in a while. That new excitement may just be the spark that "accidentally" produces that stand up triple. And those triples have a way of blowing some air back into sails.