I am confused, who is replying about what?

I have been reading and listening to Sidh Gosht recently, I also have been researching and it has come to my attention that Sidth Ghost and Japji were the last two bani written by Guru Nanak ji. Has anyone else come across this information?

oh yeh I actually remembered Tuhon Pat O'Malley, he used to hold seminars with Nidar Singh and Master Mau

I can't find it, I got this from a article on a Sikh website.  https://www.worldsikh.org/first_hand_accounts_of_the_murder_of_jathedar_gurdev_singh_kaunke   But I think this article might have something to do with it. I haven't read it though. https://www.countercurrents.org/sidhu290114.htm

Links to the book, bro?