College Board Waivers for UC?

So I have 4 College Board waivers. I apparently did not qualify for the fee waivers for the UC system.
People are telling me that I can use the 4 College Board waivers as an alternative to paying. Some of my counselors are giving me different vague answers such as that it will work, that it’s risky, and that UC will deny the college board waivers.
So I need clarification if possible.
I want to avoid paying the application fee. What happens if UC denies my College Board waivers? Will they send me a bill so that I can pay the application fee? Or will they essentially throw away my application? Is it likely that they will accept and use my College Board waivers? I am going to need a lot of info about this.
Thank You!