Dont know if you are asking a question or you have answered the question yourself, but.....
Remember when you had a stinky carpet (sorry to remind you) and I did as well.
Went back and applied Bio Green from Solutions Cornwall, from the top. Best though if you can get to the backing by either lift the carpet of inject with blunt needle ie as used to refill printer cartridges or again from Solutions.
I went back yesterday to sniff at the carpet and all I could smell was the Bio green and the customer happy too.
M-Power or Nemesis Super would be a good starter if you have any.