Sorry if I am asking a dumbass question, but what do you mean by, 'they wont disclose anything regarding the ticket submitted'?

Shouldn't you be able to see how your account was cancelled based on past tickets sent? I'm not familiar with the process, but if you go the Support page ( https://support-maplestory.nexon.net/hc/en-us/requests ) and click on your username > my activities, it should list every ticket your account has ever sent. Assuming you'd need to open a ticket to deactivate your account, the ticket responsible should be listed there alongside what the hacker claimed when sending in the ticket.