[Samsung Galaxy Tab A series Questions & Answers] elliwigy:
Not sure how many times I need to say it, you can't just "edit" the code and reset the knox counter as it is a physical fuse...

the links you posted one is some old website that still shows it installing old supersu, they don't say how or what it does, there isn't any way to reset the counter.. I imagine it is BS.. if it was a thing and worked then surely you'd see others having replicated it or at the very least talking about it over the years which isn't the case.. You can try it if you want but I would highly advise against it as they'll probably steal your money and it won't work.

as for the xda thread you linked you can clearly see it was closed by mods years ago, multiple users say it showed up as a virus as well as many saying it didn't work and was crap as well as some even saying it was a rip off indicating they were charging for it lol.. My guess is they got enough complaints that it didn't work so they closed the thread.

Yes, the code is in the bootloader for ODIN/download mode.. but A - You can't edit/modify the bootloader and have the device boot, in fact it will hard brick causing you to go into exynos usb mode or EDL mode B) The code for it to work is in the bootloader, the flags and such you are thinking about are not stored in the bootloader. If that was the case then one could just install the bootloader from a stock firmware and it would reset which isn't the case, this is because it is a physical efuse that is blown so when device starts up it write the flag on some other partition that it is tripped then the bootloader reads this flag.. what is displayed in download mode is only visual.. changing it to appear as 0x0 does not mean it is actually 0x0 since the physical fuse is blown.. not sure how hard this is to understand lol

As far as the CC mode, again, this is not something they change in the bootloader, they dissassembled the bootloader to determine how it boots and how it determines which mode to boot into. CC mode is also known as common criteria mode, samsung provides an app you can download if you want to test it out. Also, MDM can do the same thing as far as not allowing firmware to be flashed in odin/dl mode. They basically found out what the bootloader checks for when starting up or entering download mode and edited that flag to not allow flashing in odin, this is a software thing, not a physical thing. Neither of these modify the bootloader and neither of these use a physical efuse like the knox warranty bit does so they are two completely different things.

Also, just because you can change the way something appears on the screen doesn't always mean it will do what you want. For example I can make download mode say it is in ENG mode but doesn't mean it actually is.

If you need to know why the bootloader cannot be modified it's because of AVB. When device starts it verifies the bootloader against the devices root key/signature. If it is modified at all it will break this signature and since it is one of the very first things that get loaded (and is needed to load other stuff such as secondary bootloader or kernel etc. depending on the device) the startup will be killed forcing the device into an emergency recovery mode. Even if the BL is unlocked you cannot flash a modified bootloader without it bricking.

I am done trying to explain it, if you want to keep trying where experienced developers have tried for years n years and when it is technically impossible then by all means good luck and have fun.