Yeah the 3d ai is no where at that level.

Only way to make a good 3d model is 3d scan. You can do that with a regular camera or a fancy scanner. The real work (compiling images) is done on the software.

Still requires person to agree. It takes at minimum 100 photos to get a good model.

But even with a 3d model, you'd have to make a 3d print. Resin would be most accurate. Not filament.

Printed to scale.

Then turn that into a mould. Because you can't use resin moulds.

Then make a support shell mould. Which you would need to make even if mould was made directly from face but it's way easier to do it from a real face. Plus you get fine lines and pores. If you have a really high resolution silicone.

Then also someone skilled, painted it and hand added hair. Each strand is manually added. You can buy hair patches but it looks directly added. Like how it's done on high end doll heads. (But most cheap toy dolls use machines that add clumps at a time. Not single hair. or sew the hair on.)

These must have been incredibly expensive to produce.

Well, expensive for you or me.

Maybe 5k for a head. Assuming a few heads were made. That's what I would guess knowing the labor and materials involved.
If only one head. Maybe more. Since mould making process is expensive.

$6k or 7k maybe? Also more because of the NDA.

Assuming that musk or zuck are the ones commissioning these.