Found this great solution by By NCSFan001 on PSNProfiles.
https://psnprofiles.com/guide/5042-homefront-the-revolution-...There are only six total journal entries in the DLC, so you will have to find all of them. Once you pick up the sixth entry, the trophy will unlock. The first two are found in the first mission "Hostile Territory" and the remaining four are found in "Alone in the Dark", there are none in "All or Nothing".
1.When you reach the destroyed drone and the soldier that has been killed, instead of following Jill, go to the left. There will be a green shipping crate here; go through the crate and take a right to enter a small destroyed building. There are a few crafting supplies and the journal is on a table in this room.
2.After entering the pipe to the underground and going through a door, you will be in a dark room with a staircase. The journal is located on top of a box next to the stairs.
3.When you pick up the bolt cutters, there is a journal on a trunk just behind it.
4.After you split off from Vance you will find a fence and train cars to your left. You can hop the fence (or go through a hole in it) to an area with a large cage. Continue past this to a small prison area with a pneumatic pistol on the table; the journal is on a mattress at the back.
5.Immediately after the 4th journal, get back on the main path until you pass the boarded up Lombard door on your right. Check the table next to the door to find the journal.
6.Just before entering the main bandit camp, there will be a table with a few crafting materials, just before you reach the shotgun and health kit in the back of a van. Next to this table will be a couple cardboard boxes; the final journal entry is lying on top.
Fortunately, this trophy is glitched in a good way. Your progress toward this trophy actually carries over between playthroughs, so if you find four on your first playthrough, picking up any two (including the ones you have already found) on a second playthrough will unlock the trophy.