Get Handle for UI Object from a custom panel

I have a request to add an "options" button that will open a custom dialog box with various button scripts performing different functions.

One in particular is hiding some elements on-screen for what I suppose is to sanitize some information for screen snips. However when using

oUIObj.SetControlProperty "ControlPropertyName", "Visible", 0

this only works if the button is located on the actual panel containing the control and not in the custom panel - which I suppose is due to oUIObj being a handle to the custom panel itself.

So instead I used oScript.SetUIControl followed by oUIObj.HandleScriptUI(), however this only works once the dialog box is closed and the user changes tabs.

How can I use GetObject() or another method to get the handle for the main UI obj and refresh the screen from a custom panel? e.g. the "PLINES" panel from Cash Receipts Entry.