First of all them being canon dosen't mean they have to be in the same continuity, hence the books take characters and expand them and carry over concepts to the games themselves (remnant, names, technology) and help us to fill holes, for example the Springtrap in the games is the same as the books just that he took certian different paths that'd logically make em weaker.
as for your other statements, you really need to actually read the books themselves these are some heavy misconceptions.
First of all remnant is not just glowy orbs or molten spirit metal, remnant is memories the remains of the concious stated by the Novel trilogy, when these memories or this left-over concious posseses an item its considered haunted and you can melt this metal down and harness it, thats when it becomes liquid metal
so there are 3 types of remnant, Pure remnant (Shown in FNaF AR and is what makes up spirits, stated to be remains of the concious aka memories and emotions intertwined, and can be split to multiple sources), Then we have Dark Remnant whom are negative emotions and memories intertwined, and at last we have Molten Remnant the remnant you talk about being in the Novels. Also both types of remnant exists in the games
The Scooper blueprint outright shows a remnant reservoir which harnesses remnant and allows it to be melted down, it states that its a malluable liquid just like in the books.
Also btw don't get it wrong, im not judging you just that this is a common misconception that these concepts have, ill try to cover them on a blog post or something
It's cool. I know a lot about the plot of most of the FNAF books, but I haven't actually read them myself, so a blog about the misconceptions we have would be very welcome.
Oh yeah also Afton wasn't in Hell, he was just trapped in a Nightmare there is nothing that confirms it is hell.
Not only that but check this out, if you look at the OST's names in the game files or well just the soundtracks we have these.
-Hibernating Evil (Basically hibernating for humans is meant to refer to a coma, Evil repersents Afton so it's evil in a coma, pretty self-evident)
-Sleep No More (Pretty obvious since its a continous haunted nightmare that would not let Afton rest)
-Where Dreams Die (It's a nightmare, opposite of a dream again self-evident)
Not only that but we have Nightmarionnes voicelines and such, and may i mind you UCN was practically setting up TMIR1280 as a story so.
"As for one of you, the darkest pit of hell has opened to swallow you whole, so don't keep the devil waiting, old friend."-Henry in FFPS.
It's the most explicit confirmation of what UCN is that we get, and lines like "The fire within me burns eternal, and now you shall as well!" and "Leave the demon to his demons." heavily imply that it is hell. Granted, these quotes could be figurative, but so could Nightmarionne's.
Both "Sleep No More " and "Where Dreams Die" outright state that Afton isn't sleeping or dreaming. "Hibernating Evil" is more convincing, but that alone isn't really enough to persuade me.
Also, Nightmare Fredbear says "This time, there is more than an illusion to fear.". Given that his original appearance in FNAF 4 is a coma-induced nightmare, he outright states he isn't coma-induced here.
Also, I don't know what the "100 bones" thing is, so I can't argue it.
Also it's unknown how Afton killed the kids in the first place during MCI wether its a knife, or brutal stuffing or just punching them to death or something so it can't really be a contradiction and im pretty sure the Knife isn't implied in The Novella Trilogy nor ITP
He definitely didn't stuff them bc The Puppet did that, but it's implied with Vanny, who's infected by Glitchtrap and who seemingly adopts Afton's tendencies, using a knife and Purpleguy having Slasher in FNAF World.
As a whole, though, I believe that stuff from the books can and should support the games, I just don't want to composite the two. The FNAF cast can already break bones and dismember people, so most 9-C to 9-C+ books feats would be pretty consistent with the games.