With a diamond elite 2 or more membership how dies that work? In days I can bring friends how many can I bring for the special price? Is it 2 or more people or no?

It's 1 friend per card holder. The benefit of 2 or more is the price. Note, it's not often that you can bring a friend.

Good question I just have the season passes so I'm not sure to be honest.

So what's the difference between a diamond elite membership 1 person and a diamond elite membership 2 or more?

With the diamond you can bring 1 friend an you get a meal an snacks for free plus a rush pass for 1 ride an 1 pic from a ride