I think I found the event you played. If I'm right, then you tied for 1st place in your section (covering 1st-3rd places). The next highest score, at 4 points, shared 4th (covering 4th-6th). In the cross table, they sort the results in score order first, then by rating.
For purposes of cash prizes, you would share the proceeds of any 1st-3rd prizes equally (assuming those were available) and potentially, part of a class/under prize (but that completely depends on some other factors). If there were some non-divisible prizes, such as trophies, then placement is done by tie-breaks to determine who wins that/those prizes.
Does anyone understand how this works? I played in a tournament over the weekend and was tied with 2 others with 5 points out of 6 games. I beat number 1 but I ended up in 3rd. Seemed like all the placings were done by rating. The first 2 guys had a higher rating and as I scrolled down the list it was all done by rating. Why is that? Seems dumb in my opinion.