I have searched your threads, reports and support tickets. You did have a support ticket 5 weeks later, but you never mentioned the feedback. There is nothing else.
Burden of proof is on you. We do not remove feedback because it has been a long time. Had you opened a dispute 5-6 months ago we would have contacted him and asked for proof, but you did not report anything. His reply is no longer needed. Even if we contact him and he replies to say I don't have any proof, we would still not remove the feedback. It's not his responsibly to keep evidence for 6 months.
As stated, please report negative feedback when you receive it. You were online everyday and didn't report anything. That is your fault, not ours nor the user that gave you feedback.
The feedback cannot be removed.