Recovery loop, Files all gone, Finds errors but cant repair ???

[HERmAxiom]

I'm not really sure how to go about wording any of this since this it's my Fiance's laptop and not mine, so I'm going off of what info I've been able to get online & the sparing info from him himself.. He mainly uses his laptop for Cubase and similar software and to store all the music they created. Well yesterday at some point, (and I couldn't tell ya the slightest idea as to what he was doing when it happened), he said he went to log on and all of his stuff was gone, all the files, Cubase and other software, 6+ stored media files, etc. all gone. We have been tirelessly searching and trying to figure some solution out that may be able to help recover all of his files. He's been stuck in Recovery loop since it happened and we have went through all the recovery and self service options, even tried using various cmd steps to come to a solution. Nothing. For some reason he thought maybe something in the settings got messed with and tried going through the net user administrator /active: yes, nothing. ran chkdsk <driveletter>, came back with errors but were not fixed and told to fix by running /f to fix. so we did, and nothing.  We have about exhausted our resources and my brain literally hurts after 2 days of this.. Please, if anyone knows of something that we can try other than giving up or saying "***k it" and having him watch 6+ years of hard work just be completely erased from existence, we would GREATLY appreciate it. 

[WAWood]

@HERmAxiom 

Unfortunately, this is not a new issue with Win10 Windows Updates.

Read this: https://www.howtogeek.com/658194/windows-10s-new-update-is-deleting-peoples-files-again/

[HERmAxiom]

Hello, i read about this last night, but the problem is that his PC will no longer load into Windows to do anything. Its stuck on the Blue Recovery menu. He said its like Windows all together has been deleted. Is there a way to manually try to reinstall Windows through the recovery CMD??

[HERmAxiom]

UPDATE: After some extensive looking into after getting prompted that System Protection had to be enabled on :C/, I ran 

net start vss > rstrui.exe/offline:C:\windows=active

I chose what should have been a good recovery partition to go from but error (0x80070002) popped up.

This is when I decided I was going to try and Boot the pc using a USB with windows installation media on it and while trying to find out what Windows version the PC has through CMD I got the same results:

systeminfo | findstr /B /C:"OS Name" /C:"OS Version"

findstr /B /C:"OS Name" /C:"OS Version"

winver

slmgr /xpr

systeminfo

All giving me the same results of:

"...is not recognized as an internal or external command, operable program or batch file."

So i decided to try and find out what account this thing is stuck on and ran net user, this is what I got:

Administrator                     DefaultAccount                 Guest

WDAGUtilityAccount 

"The command completed with one or more errors"

WDAGUtilityAccount seems to be a part of Windows Defender Application Guard and can be turned on/off somehow but why is it the only user account present? How would I go about regaining Admin of the system without losing any hard drive data especially if no other accounts are even showing present? Can i create a new local user account that i can then activate as admin? Or am I just better off saving time and still going through with Boot loading and reinstalling a windows version? I'm sorry if I seem all over the place, just trying to take everything into account and find the simplest but correct course of action to fix this for him and my options are kind of limited since I cant get admin control of the CMD and the Windows option is not present anywhere.