That's great! I've usually had greater luck with acetone than alcohol or ink. I think I have tried them in sucession. I've stopped trying on leather pretty much because I've been afraid of lightening the leather around the stain.Wow, do I feel lucky! I tried applying small amounts of acetone and then wiping with water and a soft cloth but that had no affect on the ink marks. So I tried small amounts of rubbing alcohol followed by water and it worked great and didn't harm the bag! The faint ink mark at the top of the bag has disappeared entirely and the darker mark has gotten much lighter; I think it will be invisible after giving it a bath and conditioning the bag!
Here are some before and after alcohol pics of the ink marks: