这三个句子都正确.
what he needs is money.中what he needs 是主语从句作主语.
All that he needs is money .与All he needs is money.都是All作主语,
后面的that he needs 或 he needs作定语从句来修饰All.
all为先行词且指物时,其定从用that引导,但如果that在定从中作宾语,也可省略不要.
因此All he needs 就是省略了that的定从,因为that作needs 的宾语.
综上所述,这三个句子都正确.