can i get any help to get this guy to chsnge his feed?
Only the buyer can agree to and change his FB.
His ability to leave the neg would have been blocked had you filed/completed a UID (Unpaid Item Dispute) and the buyer continued to be a NPB (Non Paying Bidder). Sellers have 30+ days [can't recall if it's 32 or 36...you can look it up] to open a UID. Since your listing closed on June 27, that option is still availble to you if you haven't already started the process = Open a dispute...buyer will be allowed a minimum of 4 days to remit payment...if they don't, close the UID...then contact ebay to have the neg removed citing you have a closed UID against the NPB which, per ebay policy, the buyer is disallowed to leave FB about the uncompleted transaction.
"They don't keep me here 'cause I'm GORGEOUS, they keep me here 'cause I'm SMART"...Judge Judy