Our contractor hasn’t come out to paint and texturize it yet, but that’s also in the plans.

Looks like it's improperly sloped to the house, and you have minerals in your water. Put a level on it.

The concrete is leveled away from the house, towards a French drain at the back fence

I also didn’t explain very well in the original post - when I said that it doesn’t seem to absorb water in the blotchy area, I didn’t mean that it puddles or has standing water - it barely seems to get wet/penetrate. The water almost beads off as if it was rainx’ed