I guess it depends on the final drafting. Drafting the cap as "top 5 highest paid people can't make more than $500k" should solve the loophole you just wrote about.
If you sort employees by pay it is the same. But if you sort employees by power it might not be.
For example, some sales people at tech companies make much more money than mid-level managers taking home a couple hundred thousand dollars per year. Some of those sales people will make more than the senior level executives. Which one is more important and is higher rank is up for debate.
In my comment above I tried to explain a way to fix the loophole that byrneseyeview listed. Saying nobody makes more than $500k is a way to fix that.