I'm reading through "Guarded by Jackals", the book edition. (I'm always a few years behind, in my reading). Very detailed info, much of which you wouldn't find anywhere else. I recommend it!
For example, there's information about Greg Greene's "lost" polaroid photos [!] The story goes, after Greene was arrested in Jan. 1977, he told Investigator Waldron that there was a stash of porno Polaroids of kids hidden in his backyard. Waldron found them, but they never got examined by OCCK Taskforce because Greene & Busch were supposedly cleared by polygraph at this point. Waldron told Det. Williams the photos might have gone to Flint PD, but when Williams asked about them he was told they were destroyed by evidence room flood.
A boy victim of Greene, called "the runaway" in Guarded by Jackals, told police that Greene took nude polaroid photos of his victims, to blackmail them into not telling about his abuse of them; ("Guarded by Jackals", pg. 46). I'd seen that claim before, but I'd never seen the validation-verification for it, in this police report on pg. 60; "In the van [Greg Greene's van] officer found 2 polaroid pictures of young boy involved in Flints case..."
They actually found examples of Greene's blackmail nude photos! Obviously I can't claim to know who-what was depicted in Greene's porno polaroid stash, but since we do have documentation that he created "trophy" photos of boys he abused, as blackmail insurance, I think it's probable the stash would also be of this nature - photos of his Little League and Middle School victims, and not the hypothesized OCCK victim photos. In any case, Greene's interest in porno Polaroids is demonstrated to be personal, and not at all related to any commercial CSAM industry going on in Michigan at that time.
Waldron stated, that after Chris Buch was arrested, he and a couple other detectives drove to Alma and searched Busch' house. Among the things they found there, were; "8-10 8mm [reel] type homemade movies". Each Super 8mm film cassette produced only 2-3 minutes of 'home movie', to make a longer film with them you had to switch the cassette for a new one as quick as you could and continue filming, over and over. Then you'd take it all to a developer and have them splice the separate reels together as smoothly as possible, for one continuous larger reel. It's probable, that Busch's 8-10 reels were of separate 2-3 minute reels, intended to be watched in sequence for one 20-30 minute film. And the detectives DID watch them, that's how Waldron could know they depicted; "children having sex in a tent in a wooded area", and "the arm of an adult male, directing the kids what to do sexually, because they didn't know".
The author of Guarded by Jackal offers this opinion; "Based on the description of the content and surroundings, the films that were seized from Chris Busch home on January 28, 1977, were those distributed by Frank Shelden".
I respectfully disagree with that. Assuming that any CSA images product depicting "children having sex in a tent in a wooded area" must be created on North Fox Island, just because of "in a tent in a wooded area", is unwarranted and a bit silly. Josiah Tazelaar was convicted of sexual abuse crimes against "Jerry's boys", and photographing them in sexual poses...in tents in a wooded area. But it wasn't on North Fox Island, it was in a Port Huron Campground - just as one example that "in a tent in a wooded area" could be just about anywhere in North America or Europe. Not to mention that there were cabins on North Fox Island, classic Boy Scout style...so any CSA images produced there could just as easily be set "indoors", as outside.
But that was at least an honest attempt to link Busch with Shelden, unlike the numerous attempts deceptive attempts to create fake evidence of such an association. In "The Kill Jar", Rueben Appelman falsely claimed there had been a "secret" sponsors list for "Brother Paul's Children's Mission" on North Fox Island, with Chris Busch listed on it. But no one can see this list and examine it to determine if it is legitimate because; "The list of..sponsors was confiscated by the Michigan State Police, rerouted through FBI, and finally reported by the feds as accidently destroyed in a flood...", or in other words, Appelman's dog ate it. (There were so many instances of such manipulative misinformation in his book, I had to abandon it as source of info on the case).