I suppose, and hope for him, that Maloof is making, or is going to make, money out of his discovery and promotional effort. I don't know how would copyright transfer in this case. The pictures are marked Vivian Maier / John Maloof collection. He's actively promoting the collection, one day he might sell it for a good price. The claim that he hopes to recover what he spent is a bit naive. He gave up his job to promote the collection, and that seems to entirely occupy his time. I wouldn't see anything bad if he made money out of this collection which is a bit a creature of his own.
I don't really believe that Maier didn't want to become famous. I suppose it's more something like didn't hope to, or had no time - energy to strive for that kind of success. Nobody would just turn their back to fortune when it arrives. On the other hand, as Mark says, you have to mean business and actively and skilfully pursue this fortune to attain it, and not everybody make the energy investment, or is in a position to make this energy investment, to have a try.