Tracing Code Through PS JavaScript (HTML Tree)

TLDR: need to determine why the tree control field in a tree viewer setup is only returning "1" instead of "X1"

Setup a page tree control (with the HTML area for the tree and a field to use as the event field. I used the documentation and also an example from PeopleSoft (Requisition Item Categories)

It works as expected in a simple test component, but when I add it to another component (it's on a page in Level 1 the event' field change value only gets part of the code - instead of getting "X1" (or whatever, with the left side indicating what was done and the right side indicating the node) I just get "1".