You are looking for the camp and the ranger’s diary? I found it and I’ll explain how:
First of all, you only need five pages to complete the quest. As a reward, the game gave me a recipe for a stamina potion, that is, a stamina beer.
Note: Yes, I am aware that your map could look completely different. Nevertheless, I explain long and wide my way. Because there are details that are important. Maybe it will help you.
Ranger’s Diary Page – Where is his diary and camp? Return to Moria solution hint
On the map I marked Balin’s old camp. You should have found it. If I go to the right, after 3-4 rooms comes a troll. Here I pass to the right. This room has three branches. The middle one leads to the gate to Durin’s high road. The left and right branches each lead to a room with two levels and two statues each. In both rooms there is a lower level. In the left room there was an orc camp in my case. In the right room (red circle) were spiders.
I went down in the right room and walked on the circular path. There was an inconspicuous hole in the wall and I went in there.
Yes, behind the green circle it goes downhill.
There were nine new rooms down here. I took the left path to the end. In the last room I found a small orc camp and the longed-for camp and ranger’s diary.
You can’t take the diary with you. It is (visually) an open book. You just interact with the book normally.
By the way, I found a total of eleven diary pages, but you only need five.