Recently i came across such an example of attaching a BGA chip to the board.
Could this possibly have worked, or no chances no matter how careful the job is performed?
If the clock speed was not too fast and you didn't lose your mind building it, then yes it could work. I have done things like that for up to 28 pins. But for that many connections I would either ship it off to an assembly/rework house that has the tooling, or buy the tooling myself. Hand soldering that many small wires the probability of success is approaching zero.