I am trying to withdraw from the platform. However, I cannot withdraw until the final step of the trade is complete. That is the problem I am trying to solve.
Don't be naive. You're not getting a damn cent out of that site. Even if you jumped through their 'final step' hoops – which are just more ways to bleed you dry – you'd still be stuck. And besides, the site's already dead. So, how exactly do you plan to complete the trade?