That's good news. I looked at the listing and it's code and it appears that snippet of code did it's job. To update your other listings for the other missing backgrounds, you just need to replace that link to picture with the correct picture and insert the code in the same manner you did for the last one. That's everything within that "http.......jpg" text.
Here's an update to the template that removes the problem HTML code and replaces it with that CSS Script code. Your coder may want to examine what I did and add any additional appropriate attributes to that "body" style needed to compliment the prior coding.
Let me know if you test this update and if it survives a listing edit at eBay.