Clear coat scratch or something deeper. How to repair?

[Mainer82]

I scratched the side of my vehicle with a piece of aluminum. Around the scratch there was white powder like substance that I brushed off... it must have been some of the clear coat. It's about 2" long and 1/8" wide scratch. I don't think that it went down to the metal.

I used Meguiars Scratch-X 2.0 and it cleaned it up a little but I still see some white in the scratch (the paint is a midnight blue). How can I repair this? I have OEM touch-up paint pen.

I've seen this and am not sure if the clay is safe to be on the metal/paint, what do you think? http://scratchwizard.net/shop/

I've read about Quixx scratch repair kit as well but wet sanding makes me really nervous.

Here are the photos:
http://imageshack.us/a/img844/4127/8irf.jpg

http://imageshack.us/a/img7/1983/74cw.jpg

The scratch is deep but you can feel it when you rub your finger nail over it.