Good advice!
Young corns know in their genetic makeup that they better hide, run, or defend themselves, because everything wants to eat them! The babies that didn't react that way likely did not grow up to pass on their genes. As they grow, they have less natural predators, plus they get to know you and know that their environment is safe, so they have less need to hide or defend themselves. If you force him into the open, you could bring on stress problems, such as not eating, regurging, or becoming more susceptible to whatever microbes lurk about.
As mentioned, corns tend to be crepuscular, or even nocturnal. So you may have to look at him in the evenings and at night.
I have seen people try to keep snakes that want to burrow on paper or even carpet. If they really want to burrow, they often find their way under the substrate, which means that any fecal material may be under the substrate instead of on it.
One "trick" we used back in the '70s when we had a traveling reptile show may or may not help. We used to display a coral snake, which tend to be very shy. So we used a fairly thin layer of substrate to burrow in (deep enough to just cover the snake), and laid a piece of glass on top. Snakes often like to feel a solid surface against them, so the coral would often burrow between the shavings and the glass, and "hide" right under the glass, seemingly oblivious to being on display. I have never used this with corns, but it might work with young, shy corns.
