New concrete pool deck cracking

Poured 2100 SF 24 days ago. Started noticing hairline cracks, near the skimmer and a a couple in other places. They put 5" of compacted CAB road fill down, rebar 24"on center, the slab is 4-5" thick, 3500 psi concrete. They said they pump at a 6 slump. Could find nobody that would do a 5 slump.

The control joints were tooled in at 8ft, basically 8ft squares. There are hairline cracks in many of the control joints, but it seems the concrete had other thoughts. So is this just life with concrete? Not sure what else I could have done here. It's been almost 4 weeks, and most of it is still pretty dark grey and blochy. There are also some spots that I don't think we're finished that well but I may just be too picky. They did leave a 8x7 slab that is pooling 1/4" of water, they agreed to demo and repour that piece, I assume since it against a new wall they can demo it without damaging the slab it's connected too and the wall? So how do they deal with the fact the rebar in the repour will not be connected to the piece next to it?

Sorry for all the questions but I still need to pour another 1000 ft in the front. I would like to avoid similar issues.

Thank you