Dexter/Dexter4400 scammed me.

I bought a maxed zerker from him for 520m OSRS.
I played on it for a few months then decided that I was going to quit Runescape, I offered to sell him back the account at HEFTY discount, I felt like he was stalling for a few weeks, evading my messages and leading me on, then all off a sudden he had recovered the account and completely blocked me on Discord.

Screenshots to follow.

Seller's Sythe profile link: https://www.sythe.org/conversations/zerker.6998221/
Vouches if they were exchanged: -Dexters Vouches- Tibz - Vouches
Original selling thread: Buying high level zerker. / He PM'd me after seeing
Proof of payment: Screenshot is on old laptop so only proof I have is on Discord
Proof of contacting seller: Below
Discord ID + Unique Discord ID:
Any other relevant trade screenshots:

 

Proof it's their Discord: https://i.imgur.com/6dYgIKl.png

@Tibz
Sorry for your loss, the user hasn't been on sythe for 6 months and is already DNT. I've issued @Dexter with a ban.