How much is your tuition? Where do you live ? I’m guessing you have other options than AU.
You made it sound like - not being a good student in hs didn’t get you the best deal. You could have gotten a deal vs AU.
Also others get deals for various reasons - merit, ethnicity, hs performance - you don’t know why. And that bummed you when you learn of those kids. But it’s irrelevant and you will find the same in life. Other ms may work less but get more promotions etc.
Normally a school will ensure aid keeps up with tuition increases but you said your family income fell. Show them. But they don’t guarantee to meet need. And many profs telling you that you’re top - that’s great. But let’s be honest - in college, like hs, many keep a 4.0
Tell us how much your tuition is after aid and your home state. And I’m guessing we can find you lower cost alternatives.
As for RA - are you assured of this ?