If a pitcher is tipping his pitches, that's on him. If the opponent is cheating to steal signs (and relay that info to the batter), call them out legitimately. A passive aggressive comment like Maddon's is BS.
Also, whether pitches are being tipped off by the pitcher or signs are being stolen, there is an easy way to fix this (which is why I felt the Yankees, if they suspected Houston should have resolved it early instead of complaining after the fact).
Signal an outside breaking ball and have the pitcher throw an inside fastball (the pitcher & catcher need to coordinate this in advance to avoid a cross up). Do this once and no batter will trust a stolen sign.