Well, the actual hiding spot would only be placed once Poochy "found" it. Kinda like Schrodinger's cat or something. Without Poochy, the hiding spot wouldn't actually exist, so you couldn't find anything even if you hit EVERY spot on the map.
There's also a possibility that it could be timed, so if you take too long to get to Poochy and he vanishes, you'll have missed your opportunity. I'm not so sure about this one though; it could get frustrating, kinda like in Brawl when you see a CD, and you're all like, "SHINY STUFF! MUST GET!" but then you get KOed, and no one gets it, and then you're all like, "NOOOOOOO!!!" So yeah, I don't know about this one...
There's also a possibility that it could be timed, so if you take too long to get to Poochy and he vanishes, you'll have missed your opportunity. I'm not so sure about this one though; it could get frustrating, kinda like in Brawl when you see a CD, and you're all like, "SHINY STUFF! MUST GET!" but then you get KOed, and no one gets it, and then you're all like, "NOOOOOOO!!!" So yeah, I don't know about this one...