First off Im looking for cpu recommendations for the z590. I just got mine and opened the box to find the second issue. Does anyone know what screws hold down the part circled in the picture. It was missing one and the cpu pin cover popped off in transit. Luckily non of the cpu pins are damaged. Some of the components have some scratches and the brace looks like its broken where the screw goes. I haven't done an rma yet cause I'm scared it will be forever until I could get the board replaced with the same one.   

11600k and 11700k seem to be the best bet. Kinda rough that 11900k cant be recommended.

OOf...I'm sorry...the title is even "two things" and I only responded to one of them. Granted the issues you have seem more important than the second item, but alas, here's a response to that too:
 
The 11900k is not half has bad as some of the reviewers say, but it is priced high for what it is. It is priced even higher when you consider what kind of cooling is required. For example, I have a custom water loop on mine with a 420mmx40mm(thick) radiator with push-pull and an Optimus Foundation CPU block and I'm running into temperature limits at 5.3GHz all-core. I did bump up the voltage to make that fully stable, and it is possible I could reduce the voltage a little and still be stable, but with the current amount of testing I've done, that's where I'm at. I have done some benchmarks at 5.4GHz all-core and 5.4GHz on two cores with 5.3GHz on the rest, but it doesn't pass stability tests there at the voltages I've been running. It is possible I could increase voltage further and get higher clocks, but as I said, I'm at a temperature limit here. I think you could go with a liquid-metal thermal grease, but those have to be changed out more often than I'd prefer and I didn't go that route.
 
So, long story short, bang-for-buck on this platform, you'd be looking at 11400 or 11600k (if you're looking to just run the CPU limited-power and stock configuration, you could also consider the 11700k). If you don't mind spending the money and have room for lots of cooling, you could also go with the 11900k and overclock it for some really good performance. If you head on over to the Z590 FTW owners thread, you can see some of our numbers with that CPU and motherboard.
 

I purchased the 11900K and feel as though I could have spent less and gotten similar performance out of the 11600k. I think the 11900K only makes sense if you have plenty of discretionary income and you plan on overclocking it quite a bit.

Agreed