Noob here - Bad plugs? Please help?
 

Hello, I just bought an Audi as my first car because I've always loved Audis, it's a silver 2003 Audi A4, and it's been really good to me until recently. There has been a knocking sound coming from under the hood when I drive and it sounds pretty scary so I brought it to my brother who's good with cars and owns a Vette. My brother looked at it and said the thread bearings are literally gone, they must have exploded and ripped the camshaft sleeve because it was completely frayed. I'm not a pro so I don't understand what a lot of that means, but I knew anything having to do with camshafts is an expensive repair, so I had him do the work. He said the cheapest way to do it was to replace the standard spark plugs with special designer ones he made himself that he designed to spark extra-hard to clean any fuel gunk out of the cylinders that could be causing the knocking. He replaced the camshaft sleeve for free and gave me his spark plugs and I installed them myself because it's fairly easy with these cars and I didn't want to pay him for any more time than I needed, and we don't get along very well as it is. As soon as I started it up, it started knocking really loud and then shut off. And I haven't been able to turn it back on. My cousin has been driving me to and from campus since then but I can't have him do that forever. How can I solve this issue? Was it the custom plugs? If it was, I don't think I can ever trust him again. Someone please help, and once again sorry for my stupidity.

Is this for real?