Create a Site is not formatted correctly

Hi, I noticed that my "Create a site" page is not formatted correctly. I'm not sure where I go to format this page as it seems to be dynamically generated.

I've taken a screenshot of how it looks:

You can see that the left has no padding at all and the the sidebar is on the right (I wanted it on the left) and pushed down under the content.

I tried the Twenty-Twelve theme, and it looked OK, so I think it's a theme css issue. But the Twenty-Twelve theme doesn't have a sidebar, so I can't fully tell.

All the other pages (buddy press, etc...), for the most part, look fine.

If it IS a theme issue, I have no idea of where to even start to fix it because it's dynamically generated. Not sure what CSS is even being used.

(I have another ticket open with this same question, but I haven't heard anything back from it in 3 weeks. So I hoped asking the question again would get an answer)