HELP! No Bluetooth Hardware Found (2020) macOS Catalina 10.15.5

My mac: Macbook Pro Late 2012

macOS version: Catalina 10.15.5

The problem:

It shows Bluetooth is disabled with the icon greyed out and a zigzag line across which means bluetooth is unavailable.

In About Mac > System Report > Bluetooth it gives "No information found"

The whole bluetooth Preference Pane has disappeared from System Preferences.

I am studying IT in college so I know a little bit about software. I used to connect my Boat Rockerz Bluetooth earphones and never once got any issues with bluetooth. 

But recently after updating to Catalina 10.15.5 and connecting my new realme Bluetooth earphones they did give an issue whenever they got paired like: getting connected but audio still coming out of the mac speakers. One morning I connected them again and the same happened so I turned Bluetooth off. But since then it never turned on.

Solutions I've tried:

I've tried deleting plist files.

I've tried SMC and NVRAM resets.

I do not get a debug menu from pressing shift + option + Bluetooth menubar icon. It only gives me an option of "Open packetlogger" which doesn't even do anything.

I reinstalled an older version of Catalina 10.15.4 which was fine before but the problem still exists.

I installed Bluetooth Explorer from additional tools for Xcode 11.5 and ran the Modifier Factory Reset, but it didn't work.

When I open System Preferences, it shows these errors on the Bluetooth Explorer Event Log:

Jul 12 23:37:26 Khushbu AccountProfileRemoteViewService[734]: objc[734]: Class AOSUISpyglassAccountChangeHelper is implemented in both /System/Library/PrivateFrameworks/AOSUI.framework/Versions/A/AOSUI and /System/Library/PrivateFrameworks/AOSUI.framework/Versions/A/XPCServices/AccountProfileRemoteViewService.xpc/Contents/MacOS/AccountProfileRemoteViewService. One of the two will be used. Which one is undefined.

Jul 12 23:37:26 Khushbu com.apple.xpc.launchd[1] (com.apple.xpc.launchd.domain.pid.walletAvailabil.739): Failed to bootstrap path: path = /System/Library/PreferencePanes/Wallet.prefPane/Contents/Resources/walletAvailabilityCheckTool, error = 2: No such file or directory

I have no idea what went wrong and no amount of googling is helping fix this. I am not in a state where I can clean install macOS again as of now and neither do I have any backup options.

By my incessant googling, I found that this is an issue faced by countless other Mac users since 2008. Not just this but lot many other bluetooth issues. They have no solutions and require normal people with lay man knowledge to delve into plist files and what not.

An issue almost 12 years old or more and still no solutions. I am sure it is a software issue since it began only when I turned off bluetooth that morning.

Since it is a 2012 machine I will not be getting the Big Sur update that could've probably fixed it. Now what should I do?