disputed offsite already

Scammer's profile link: FortuneSeekersGG
Amount scammed: 12b (8.9b on one account)
Discord ID + Unique Discord ID:
fortuneseekersgg_12033 1270046090409935046
Proof that it's their Discord: imgur.com
Explanation of the trade: Had them get a rune pouch on my HCIM that was linked to my main jagex account and after going to bed and waking up I saw he was logged into my main account, spam messaged a few times trying to get them off and see what they were doing until I was able to log back into my account and see the 12.01B GP I had on the account was gone and they were trying to still sell some of the untradeable items I had on me
How they scammed: Logged into my main after going to bed while doing work on another account linked to a jagex launcher and then stole all the wealth on other accounts.
Other relevant trade screenshots: (my bank after it was and the last picture is before it was stolen) imgur.com

 

I would also like to mention this did not happen over discord this happened over eldorado.gg where I purchased the boost at first. I never had contact with them on discord but their discord was posted on sythe.