Jeffrey, if you can still see the mark after more e-tank, I encourage you to go ahead and season it. If it were me, I would use Crisco and season it at least 3 times, going to 500 for an hour to get carbonization. I'm betting the mark will disappear as the pan gets black from seasoning, in much the same way as the pale sunglasses-area around your eyes disappears as you get more sun on your face.
Then, put the pan away if you're still bothered by it. I'm guessing you'll feel differently about it after some more time collecting.
(I'm no expert--this is just my take, ok?)
I agree with Donna...e-tank the crap out of it, maybe another 2-3 days, and then if it's not to your liking, season the crap out of it. It's going to eventually disappear, once the exterior begins to blacken..........Good Luck !