Why didn't Marritza expect the Bajorans to catch on to his lie? Given what we later see of the Cardassian legal system, he must have expected only a cursory investigation followed by swift punishment. In fact, what we see of the Bajorans attitude, he was also probably right that they wouldn't have done much of an investigation either. Only Odo (who's naturally meticulous) and Starfleet (with a more neutral perspective) insisted on making sure.
Given that one random Bajoran is willing to stab Cardassians to death just for being Cardassian, you have to wonder what Garak puts up with day to day. At least Garak is more likely to see the trouble coming.
