So, when you get into the Blood Pit, you have to interact with Charged and Uncharged Lucents.
The first one you pick up is a Charged one.
You can also find an Uncharged one, and charge it, and have 2 charged lucents in your inventory, while on the ground floor.
But if you do this, the game will not allow you to place one by the portal that leads to the balcony, so you can't take the other one to the upper floor and place either of the lucents in the TWO places you have to place them there.
I am currently stuck with no way to progress because I have 2 charged lucents, 2 places on the balcony to place them, but an inoperable portal on the floor so I can never reach the balcony.