I'm just gonna say it, this makes me sad. I wish there was a way to salvage this, but I doubt it. I can't figure what would cause the discoloration this badly? Soaking it? Eta- I'm wondering if it's soap b/c I can't imagine water doing this? Poor Gigi, I hope she lived a good life. 
http://www.ebay.com/itm/COACH-65TH-ANNIVERSARY-LARGE-GREEN-LEATHER-LEGACY-GIGI-TOTE-HANDBAG-11131-/121082229219?pt=US_CSA_WH_Handbags&hash=item1c311031e3

http://www.ebay.com/itm/COACH-65TH-ANNIVERSARY-LARGE-GREEN-LEATHER-LEGACY-GIGI-TOTE-HANDBAG-11131-/121082229219?pt=US_CSA_WH_Handbags&hash=item1c311031e3