Does adderall (dextroamphetamine and racemic amphetamine) work for idiopathic hypersomnia?

Yes: Adderall is a wake promoting drug in the amphetamine class - it does work for idiopathic hypersonic along with other drugs such as ritalin, (methylphenidate) dexedrine, pro vigil and nuvigil.

It might: Stimulants are often used to help treat disorders of excessive sleep. One potential difficulty is the possibility of becoming tolerant to the effects over time. I would recommend you seek out a sleep disorder clinic and let them guide in with respect to best treatment practices.