I tried fixing my girlfriend’s slow PC by updating old drivers and now Secure Boot breaks Windows (Valorant won’t run unless it’s OFF) plus (she will kick my asss if i dont fix it)

Question

So I was trying to help with a PC issue and somehow made it worse.

Her PC was feeling really slow, so I started cleaning it up — deleted temp files, checked updates, and then went into drivers to see if anything was outdated.

I found an Intel graphics driver update from like 2018, so I thought that might be part of the problem and installed it. After that, I also ran some system updates and restarted the PC.

Now the issue is this:

If Secure Boot is OFF, the PC works completely fine

If Secure Boot is ON, it won’t boot into Windows at all (it shows something like “boot security blocked this boot” / black screen)

And because Valorant requires Secure Boot ON, the game won’t launch anymore

What I already checked/tried:

BIOS is UEFI mode

Disk is GPT

Restored Secure Boot factory keys

Disabled Legacy Support / CSM

Reinstalled Riot Vanguard

But nothing changed:

Secure Boot ON = PC doesn’t boot

Secure Boot OFF = PC works but Valorant can’t run

It was working before I started messing with drivers and updates, so I’m pretty sure something got messed up during that process. like can i go back to the version before the one i upgrade . or like if i reset my pc to factory siiting and deleted everything will this work?

Has anyone seen this before or knows how to fix it without reinstalling Windows?