What happened to break the bottom cover and the palmrest?  Any drop or impact significant enough to do that level of damage likely damaged the hard drive (which would explain the diagnostics taking that long). If the OS was installed on the NVMe drive, remove the hard drive and see if the system will boot properly.  Failing that, you can prepare Windows boot media from Microsoft: [URL] and use that to install the OS. There is of course the possibility that other components were damaged in whatever caused the need to replace the  chassis parts -- including the system board itself.  
Hi guys, I'll let you in a few details before getting to the main problem, I have a Dell Inspiron 15 5570 with 2tb HDD and 500Gb SSD PCIE NVME installed, the bottom cover and the palm rest were broken, so I had it replaced. The problem started after replacing it. When I opened the laptop for first time(after the part replacement) the video and audio were lagging and it took a lot of time to boot. So I contacted dell service and they told me to install the video audio drivers and bios as well. After installing the bios the laptop restarted and took like hours to boot up. Unfortunately the power was out and battery drained out without windows loading. The next time i charged battery and started my laptop it is stuck in a boot loop and I get blue screens with following messages that are attached. [IMAGE]when i click f1 for recovery this pops up[IMAGE]Next this one[IMAGE] Then I go through dell support and dell community. Then run a full pre boot diagnosis for 7 hours and turns out all the hardware and memory components are working fine as new. Then I understand that this is a OS problem. So I search again in Dell support and Community try making a USB from Dell OS Recovery Tool. Does not detect. I read in community that you can download the OS .ISO file from Dell using service tag so I do that and make a bootable USB using Rufus as said. Still no detection from Laptop. But when i create a USB disk from windows media creation tool and see, it gets detected. But I don't want a inactivated windows. I had Windows genuine and MS Office for lifetime from Dell. I m freaking out because I paid for fixing outer damage of laptop and got into this mess. I need my laptop fixed so that I can finish my projects and College Work. Please help me out in fixing the laptop.
Dell Inspiron 5570 Non Bootable USB using Recovery Tool and stuck in Boot Loop