You are comparing the
internal driver version vs
package version, which don’t align numerically. Package version
18.7.7.1013 WHQL includes IaStorAC 8.37.7.1013, which is the RST Premium driver that you currently are using. This package also includes a VMD driver, but your laptop uses a HM370 chipset, and, this chipset supports RAID mode but not VMD. I was wrong about that part... sorry for the confusion. Package version
18.8.0.1004 WHQL does not include IaStorAC even though the INF inside this package does include the matching Hardware IDs thereof. On systems that have a legacy controller in their chipset (such as the one that's inside your HM370 chipset), all this newer package does is install the UWP app. I.e.,
this one.
AFAIK the correct guide for the XPS 15 9570 is this one:
Switching between AHCI and RAID on the Dell XPS 15 (9560)
If you forget to change the BIOS setting back to AHCI after you changed it to factory default (i.e., RAID) it will BSOD with INACCESSIBLE_BOOT_DEVICE because Windows tries to load StorNVMe instead of IaStorAC, and fails because StorNVMe needs AHCI to work. When this BSOD happens you can just enter the BIOS again to change the setting back to AHCI. Then Windows boots normally again. The only "issue" is that, by default, Windows restarts the system automatically each time after a BSOD. So, to avoid getting an endless BSOD loop, you might want to change this registry setting if you haven't done that already.
reg add HKLM\SYSTEM\CurrentControlSet\Control\CrashControl /v AutoReboot /t REG_DWORD /d 0 /f