There was 4 missing before, Fallen 3.6, 3.7, 3..8 and 3.9. These have all been found inside the new Wrath of the Machine Raid. Below is a text and video guide on where to obtain them.
[b]Dormant SIVA Cluster: Fallen 3.8[/b]
Video: https://www.youtube.com/watch?v=kIi0EpWmiwI
Text Location: This one can be found towards the end of the first jumping puzzle in the raid. Once you reach the pathway to the boss room, instead of going into the vent you want to continue down the jumping puzzle. Follow the ledges all the way back left corner of the area, and at the top is the Dormant SIVA Cluster.
[b]Dormant SIVA Cluster: Fallen 3.9[/b]
Video: https://www.youtube.com/watch?v=JhMHex2Lt5s
Text Location: This one can be found after the Vosik encounter in the second jumping puzzle. Right at the start jump on top of the . [Credit to Deus JayP for this find.](https://www.youtube.com/watch?v=vi20mU6uMpU)
[b]Dormant SIVA Cluster: Fallen 3.7[/b]
Video: https://www.youtube.com/watch?v=u5sTWvYkMlA
Text Location: This one can be found directly after the Death Zamboni fight. When you drop down to the chests, over the side of the cliff to the right is a Dormant SIVA Cluster hiding.
[b]Dormant SIVA Cluster: Fallen 3.6[/b]
Video: https://www.youtube.com/watch?v=OCatizAgZIU
Text Location: This one can be found in the first room after the Death Zamboni fight. When you enter the dark Rasputin like room for the first time, at the bridge you can drop off a ledge to the very left. Jump across these and the Dormant SIVA Cluster is there.