I have my old main OSRS account that was hacked a few months back. The hacker logged onto the account today and admitted to hacking the account (all of this is screenshot and proof). This was an old account that I used from a long time ago and the email associated is not active anymore. Multiple appeals were submitted for this account before today and all were denied... but NOW I have proof of the incident. Where can I submit this proof to get my account back...?
If you were talking to this player in-game, you should have used the in-game report system as that captures the chat record and account activity. How to report a player Screenshots cannot be submitted as evidence as they can be edited and Jagex will not act on them.
Also, reporting another player on the account will not result in the account being returned to you. Jagex would lock the account but you would still have to recover it.
You need to prove that YOU created the account to get control of it again. If you are being denied recovery, always click on the link in the 'deny' email to find out the reasons as that is the information you need to improve on your next attempt. Have a read of the Denied password resets support page for tips about the kind of information Jagex want to see in the recovery form.