If you defer at UR for next year it is like enrolling there, but not attending until next year. You can’t deposit somewher else and take classes somewhere else.
You can get a job at a restaurant, store where ever if you take a gap year. You can make about $6,200 a year before it would reduce Pell I believe. Yes, the work study income at UR would not count against your federal aid eligibility for next year’s FAFSA.
The plan your sister and mom came up with sounds like a bad idea. How would it help if your mom would take online classes? The transcript is in your sister’s name.
Sounds like your sister is not graduating on time if she has been in school 6 years and not finished. She is running out of aid, there is a limit of how many semesters you can get Pell for. Your sister should have worked in summer and paid CC tuition out of pocket and saved Pell for 4 yr university. Also the loan limits for junior and senior year are $7,500 a year. If your parents applied for plus loan she could get another $4,000 I think. If she worked she should be able to come up with the $15,000.
Your sister needs to talk to the FA office of the school to see what she needs to do to get aid reinstated. How many credits does she need to make satisfactory academic progress? If she has any classes left to take at CC maybe she can pay out of pocket for one or two and work to earn the money? The goal is for her to graduate and get a degree.
But not by falsifying information. There is a way to get back on track, sometimes students have to retake classes they failed or work a semester to save up money before continuing your studies. Or pay for some classes out of pocket to regain eligibility for FA.
Also if you tutor someone and make over $400 a year you need to file a tax return. It is self employment income.