If this is the case, it seems kind of easy (if not a tad invasive) to solve. You have the MLB watch over the balls in a secure area, and when the pitcher and catcher go out, you check their pockets to see if they have anything like Pelican Grip Dip. If they do, they can't go out.
Checking pockets isn’t enough. Pitchers have been hiding the substances on their hats or gloves or other sneaky places for years. It’s not like they just bring a jar of spider tack out there with them
It is better than nothing. But you've also got people going on and off the field frequently and a strong incentive to cheat. If your five second check is circumvented it's no longer that much better than nothing.
