The lower anchors in 3C are overlapped into 3D in a way that if you install a car seat in 3C with the lower anchors you can not put anyone or anything in 3D. So long as you are OK giving up 3D, you may install a car seat in 3C with the lower anchors. However, you can not use the lower anchors to secure a booster in 3C as the booster will sit on top of the seat belt it needs.
3rd row has 4 LA all spaced 11 inches apart. Can install 2 car seats (3D & 3P) with LATCH, or 1 car seat in 3C w LATCH. Installing one car seat with lower anchors on either 3D OR 3P will take up both that side seat AND 3C. To try and get 3 car seats in the 3rd row, install in 3C with lower anchors and use the seat belt for 3D & 3P (and tether all forward-facing seats).