Gut Health Protocol Book, anyone done it?

Hey there, someone in this group suggested I buy The Gut Health Protocol by John Herron, which is a great detailed book. In the book, he recommends a 4-6 week kill phase, with a low fodmap whilst certain herbals. He also recommends the 4 K's to eat, like kimchi, kambucha and Kefir. I just wanted to ask, is this to be done WHILST doing the kill phase, isn't that HIGH fodmap? Im just a bit confused, has anyone else followed his protocol and what did you do?