I will not ask anymore questions as I'm afraid of the answers!
My advice is that you do a Full Monty to at least get you back to normal...
Back up everything on your phone and sd card.
Format your internal memory and sd card memory.
Factory reset your phone and re-flash the stock Samsung MH8
firmware to get rid of the aborted root.
4. Re-boot your phone and re-download your apps but NOT the settings. These you will need to do again, afresh.
Put your sd card in after turning your phone off and the re-boot. After this you can copy all your data, music, photo's, etc; back on but not any settings.
I am afraid that this will not unlock your bootloader or get rid of Knox but at least you should have a working phone that may be able to be rooted in the future and accept custom ROMs.
"Losing your phone", is not something I can condone on this forum. Besides which, with your luck, you will get another one with MH8 firmware on and you would be where you are now!