Longer answer: The cell and norm operators will have as many dimensions as there are dims in the matrix/texture coming to the jit.gen/jit.gl.pix's first inlet. So if you are sending the "jit.bfg 3 float32 10 10 10" to the first inlet, then cell, norm etc. will be 3-element vectors. You can pull out individual elements (dims) of the vector using [swiz x], [swiz z] etc. (or [swiz 0], [swiz 2] etc.). And you can pack values into bigger vectors again using [vec] and [concat] operators.
So jit.spill is only showing the first slice of the 3rd dimension (the lists should have 27 elements, not 9!). A quick test of swapping the [norm] for [noise] in your patcher verifies that the jit.gl.mesh is only receiving 9 points too -- I think jit.gl.mesh can't handle 3d matrices either.
In general support for 3D matrices in Jitter is much more limited than 2D matrices, unfortunately.