VR and Leap Motion

Hello everyone. I have some problems that i have a hard time to understand with the utilisation fo the leap motion and virtual reality.
It’s pretty simple in theory. I’m just trying to place something in front of my hands. But there seem to have a huge difference between the position of my hand and it’s visual représentation in my 3D world. I don’t know why and it’s what i’m trying to understand.

In the first photo, the dots you can see, are the drawn debug sphere of the elbow, wrist etc etc. Photo 2’s a part of the BP for me to be understood.
Thanks in advance for the help.

Edit: I think it’s link to this :