One of the reasons why, as a DM, I like the Passive Perception mechanic in 5e. It takes some of the thrill of a roll away from the players, but it gives me the tools to resolve these sorts of situations without tempting the players to metagame.
What the hell?! I didn't know about this either! I guess it makes sense from a realism standpoint, but damn, that's good to know that its possible in game as well.
You can also summon scratch and he will find it for you. Apparently he even finds chests that don't have a visible survival check. But I can't confirm that because I never have him summoned.