Maybe a few things to check but I would not disable Secure Boot on a UEFI system, but make sure your Bios is up to date.. You do have to make sure and boot the Install Media in the UEFI configuration.
If this is a Business Desktop, might it have an special protection utilities to keep Windows from being removed?
Could you go back to Diskpart and type the command below and get a screen shot.
list disk or for short, lis dis
If you find a Disk 4 or the one being referenced, you might then run the command below in Diskpart, which uses only the first 3 letters of the command..
sel dis X where X is the disk number of the OS drive..
det dis
Do you run an xBox?
DISKPART> list disk
Disk ### Status Size Free Dyn Gpt
-------- ------------- ------- ------- --- ---
Disk 0 Online 931 GB 1024 KB *
Disk 1 Online 1863 GB 1024 KB *
DISKPART> sel dis 1
Disk 1 is now the selected disk.
DISKPART> det dis
Samsung SSD 970 EVO Plus 2TB
Disk ID: {D6563CED-295E-4D56-9665-488962FBB4C8}
Type : NVMe
Status : Online
Path : 0
Target : 0
LUN ID : 0
Location Path : PCIROOT(0)#PCI(1B04)#PCI(0000)#NVME(P00T00L00)
Current Read-only State : No
Read-only : No
Boot Disk : Yes
Pagefile Disk : Yes
Hibernation File Disk : No
Crashdump Disk : Yes
Clustered Disk : No
Volume ### Ltr Label Fs Type Size Status Info
---------- --- ----------- ----- ---------- ------- --------- --------
Volume 1 C Win 10 NTFS Partition 899 GB Healthy Boot
Volume 2 NTFS Partition 498 MB Healthy
Volume 3 E PriBackup NTFS Partition 963 GB Healthy
Volume 4 FAT32 Partition 100 MB Healthy System