They will still need a chassis/engine before they have a viable car, and there's been no real external indication of them either developing that in house or partnering with/purchasing someone that can provide that expertise.

.. at least I think that's what the question is about.

I thought they just made a deal with CMU and then proceeded to recruit everyone to leave.

But they still need the actual vehicle hardware, chassis, motor, etc knowledge. CMU's robotics division is just provides the self-driving component.

Building a car is 5-10 years out. It's a long, slow process. And you need to clear dozens and dozens of safety protocols.

Developing a car is very expensive.