How can I make triangles in material editor face a specific point, rather than the camera?

I have a modified a Lidar project : https://forums.unrealengine.com/deve…ce=&viewfull=1

I have changed it so that the Lidar is rendered out from a static camera in the scene, four cameras to be exact, they capture depth from the inside of the inner side of a sphere see here:

[ATTACH=JSON]{“data-align”:“none”,“data-size”:“medium”,“data-tempid”:“temp_122756_1510683747920_889”}[/ATTACH]

A 2DSceneCpature component saves the depth to a render target, I use this in a material to reposition a long chain of quads that I have generated at run time.

This works correctly, however, each of the quads rendered on the sphere always face the player camera, done using this:

[ATTACH=JSON]{“data-align”:“none”,“data-size”:“full”,“data-tempid”:“temp_122757_1510683721841_560”}[/ATTACH]
I would like each of the quads to face the centre of the circle where the depth is being captured from.

I know to get that direction it is the Origin-WorldSpacePosition, but I do not know how to use this in Transform3x3Matrix to make that position face the origin.

Any help would be appreciated, or point me in the direction of a tutorial so I can understand the manipulation of the world space positions using the transform matrix.

The whole mat for reference.