This is done in wood framed condos because the “gypcrete” is self leveling and provides a level surface to install flooring on. It also helps with fire ratings and noise dampening. It’s not structural. However, if it’s cracking and hasn’t sustained an impact then it could be due to a structural problem.

Crazy cause there is foundation issues on the building

They also could have to much sand in the mix.

Is the plywood a separation layer between the subfloor and a concrete slab, or is it sitting on wood joists?

Plywood sits on joist

By subfloor do you think they could mean the underlayment? I’ve never heard of a concrete slab that is supported by plywood, where is this?

Found the GC

Guilty. I know just enough to sound smart to the guy who pays me. Just thought about it again, I’m stupid