I discovered that you can use pane.setSplitFraction() and you need to call it on the python panels “resize” event, then you can ovveride whatever automatic resizing that takes places, in case anyone else runs into the same thing!
I discovered that you can use pane.setSplitFraction() and you need to call it on the python panels “resize” event, then you can ovveride whatever automatic resizing that takes places, in case anyone else runs into the same thing!