Impossible to install network and other drivers on Windows 10

Recently a friend of mine told me that all of a sudden Wifi had stopped functioning on her Asus X541U laptop. She gave the computer for me to fix and for the past couple of days I have tried diagnosing what the issue is. I have tried many different solutions I have found on Google but nothing has worked this far. The computer's operating system is Windows 10 Pro 1809 running on a 64-bit processor. Here's a summary of what I've found out and what I've already tried:

Device manager shows quite a few non-functional devices listed under "Other devices" with a message "The drivers for this device are not installed. (Code 28) There are no compatible drivers for this device." Initially the non-functional devices included both Ethernet and Wifi (Realtek RTL8237BE Wireless LAN 802.11n PCI-E NIC aka VEN10EC&DEV_B723&SUBSYS_172311AD), so I could not connect to the Internet to update drivers through either means. I had a Huawei USB dongle at home, so I tried that, too, but the dongle also ended up on the list of non-functional devices, though seemingly the setup process was completed. When I launched the dongle's interface program, it seemed to identify an existing cellular network but clicking on "Connect" gave me a message "The device has been disconnected or is unavailable". On another Windows 8 computer, the dongle works fine.

Subsequently, I uninstalled all USB and network devices to see if Windows could automatically reinstall them correctly. After reboot, I opened Device Manager and found the same (or possibly even more) devices listed under "Other devices" as non-functional and with the same error message. This time, it was even slightly worse, as devices which had previously displayed a full name (such as Realtek RTL8237BE) now showed up only with generic names "Network adapter", "Bluetooth Radio", "Ethernet adapter" etc.

My third step was to download the latest Realtek WLAN driver from Asus's website with another computer and copy it to the problematic computer with a USB drive. I launched the installation program, which seemed to complete, but when after reboot I checked the Device Manager again, nothing had changed. Looking at c:\Windows\INF\setupavpi.dev.log, I see the following lines:

     idb:                {Register Driver Package: C:\WINDOWS\System32\DriverStore\FileRepository\netrtwlane.inf_amd64_cd47a8276528da6b\netrtwlane.inf} 13:57:08.749
!!!  idb:                     Failed to create driver package object 'netrtwlane.inf_amd64_cd47a8276528da6b' in DRIVERS database node. Error = 0x00000002
!!!  idb:                     Failed to register driver package 'C:\WINDOWS\System32\DriverStore\FileRepository\netrtwlane.inf_amd64_cd47a8276528da6b\netrtwlane.inf'. Error = 0x00000002
     idb:                {Register Driver Package: exit(0x00000002)} 13:57:08.764
     sto:                {DRIVERSTORE IMPORT END} 13:57:08.780
     sto:                {DRIVERSTORE IMPORT END: exit(0x00000000)} 13:57:08.780
     sto:                Rolled back driver package import.
!!!  sto:                Failed to import driver package into Driver Store. Error = 0x00000002
     sto:           {Stage Driver Package: exit(0x00000002)} 13:57:08.780
     sto:      {Setup Import Driver Package - exit (0x00000002)} 13:57:08.780
!!!  inf:      Failed to import driver package into driver store
!!!  inf:      Error 2: The system cannot find the file specified.

Before these lines, everything seems to be progressing smoothly. I also tried installing the downloaded driver by clicking on "Update driver" in Device Manager and manually selecting the appropriate path but that, too, generates the same error messages in the log plus a user message saying "The system cannot find the file specified." I've tried copying the driver files directly to C:\Windows\INF\ as well as C:\WINDOWS\System32\DriverStore\FileRepository\netrtwlane.inf_amd64_cd47a8276528da6b\ (which is mentioned in the log) but neither action has resulted in any improvement. I have also launched the built-in Internet and Network troubleshooters and done a Network reset but to no avail.

As I said above, even the USB dongle driver fails to install as well as other devices, including a bluetooth radio and a webcam, so I don't think the problem is directly related to the Wifi driver but there is another issue on some deeper level. I did launch sfc /scannow, which got stuck at 96%; I pressed Ctrl-C after which it resumed scanning, got stuck again at 98% and after another Ctrl-C continued to the end. It didn't find any integrity violations and Chkdsk didn't find anything, either. The computer has Bitlocker and a VPN service called NordVPN, which had its own virtual driver listed under "Network adapters". I uninstalled the VPN driver just in case it would interfere with physical network adapters but didn't see any change. I also uninstalled the latest Windows updates but that didn't change the situation either. There is no system restore point which would predate the first occurrence of the problem, which was already two months ago. The computer has ESET Endpoint Antivirus, which was up to date the last time the computer was able to connect online. Disabling the antivirus during driver installation doesn't change anything, and trying to install the driver in Safe mode with networking enabled results in an error message saying "Unable to access the Windows Installer service". I would really not want to do a system reset, as the computer has quite a few installed programs including Bitlocker which encrypts the whole hard drive and could make reset a more complicated process. Any ideas?