I don't know whether Authentic-luxury.com is still doing authentications. You can ask them.
Please post a link to the listing as well as the seller's ID. (Use the format requested in the first thread of the post.)
We like to look at the seller's history.
I see you revised your post to include a link to the listing.
Auth.
Coach Blue Canvas & Leather Signature L HoBo Bag
Item number: 250684551167
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=250684551167
Seller: jpcurtis777
You're absolutely correct about the bag being an awful fake.
The seller needs to know that if she's going to shop at estate sales, she's responsible for authenticating her items.
Her feedback is already bad and in this case, her lack of willingness to do the right thing with you has (IMO) earned another negative feedback.
http://toolhaus.org/cgi-bin/negs?User=+jpcurtis777&Dirn=Received+by&ref=home