"There's probably a dozen other paths, leading out of this cellar alone." points out Cloverleaf. "You may have noticed how hard it would be to spot the tunnel we came in by from this end, if the door were closed? What are the odds that they stopped at a mere one disguised tunnel?"
He reaches up to put a Lock-Tight spell on the trapdoor, while it's within reach, then hops off the barrel and strolls to the nearest wall. "Fortunately, there's a technique for finding secret doors. It's quite simple - all you have to do is cut out the frantic searching for twenty minutes for the latch, and skip straight to the point of nonchalantly leaning against the wall, which almost always opens the door if there is one."
He demonstrates this technique by nonchalantly leaning on a random bit of wall.