Cabot opened his mouth to answer with a reflexive 'Of course not!', only to catch himself. One could certainly argue that hunting down Pleo and dragging him off to Giotto counted as mistreating him, especially with how miserable Pleo was during his stay... But, he also befriended Pleo and eventually convinced Nagant to let him go when they found him again on Haipheh. Surely none of that would have been possible if the Empire was bad.
Besides, they let Pleo's friends go free when they got to Giotto, which is certainly something the Company would not have done. They probably would have just shipped them off to Nagrobek, but instead Pleo's friends got to see the best city in all of Anyilla! Not to mention that the Company's trying to kidnap Pleo so they can use him as a weapon, whereas he and the rest of the crew only took him to Giotto in order to save him from them. With how negative Bahamut always is, does all of that really count for his definition of mistreatment?
"N-No. Nothing that didn't work out in the end."