Splitting a tree into variable branches

I have set up a script that applies a hex grid to different panels and sizes the hex grid differently for each panel. Ultimately, I'm pulling points out of these hex grids (at both line ends and polygon centers), and I would like to maintain the data structure for these points so that I can keep them grouped by panel. The outputs of the hexgrid command do this, but they go even further by subdividing the grid into rows and columns. Unfortunately, this adds extra branches to my tree, which for the life of me I can't collapse back into the main branches.

I've tried every single way I can think of, and every example I've found, but still nothing. Essentially, all I'm trying to do is combine the last branches into their parents....doesn't really seem like it should be so difficult. What's key, of course, is that the values in those are both different and subject to change, so I can't do any even tree separation.

The end result of this thread (http://www.grasshopper3d.com/forum/topics/break-single-path-into-mu...) seemed to be the closest to what I had, but alas, it did not work...nor did any Path Mapper setup I could come up with, though I feel this might be the way to make it work.

I've included the definition and the Rhino file, along with a jpeg that shows that I've gotten painfully close using the Split Tree command, but it isolates the grid point sets one by one, without allowing me to group them in the same command....

(n.b.: ignore the overlap of the points. That all gets fixed later in the script.)