Throughout the game, the player is informed that opening the door to Moria involves several requirements:

You need to collect 5 gemstones

You need to collect the keystone

You need the Elvish Book

You need the Amulets

It also heavily implies that you need to talk to Elrond so that Gandalf will know that you want to meet him there at the door.

Well, about that.

Let's say that Frodo shows up at the door to Moria with nothing on his back, he never met the hobbits, etc, etc.

Who's there? Why, it's Gandalf. What does he say? He says we need the amulets and the gems. Now, a casual player will heed this advice and go get them.

We aren't casual players.

Let's say you come over to Gandalf and you haven't collected the amulets. Instead, you show him the book. Instead of telling you "yeah, buddy, you forgot the amulets", he instead tells you the riddle explaining how to put the gems in the door.

So you don't need the amulets. Hey, you don't even need to meet Elrond. Just, show up at the door and hand Gandalf the book.

Let's go a step further. You don't even need the book. Wanna know why? You can step up to the door and start shoving gems into it. Ignore the wizard, act like you know the combination and just shove 'em in the door.

If you know the right combination of gems, that's all you need to enter the door to Moria.

The combo is: Keystone, Purple gem, Violet gem, Yellow gem, Red gem, Green gem, then Keystone again. If you do that, the door opens regardless of books or amulets.

Yeah I determined you didn't need that junk when I first routed glitchless. Thought you still needed the Scrolls though so that's good to learn we don't.