Yes, using the Browser-Workaround to access objects, that Autodesk tries to render inaccessible works fine: I had that Idea before too to access the publication tweaks. Didn't see, that the parent node's native object is the same thing as the parent of my select set's item.
That's because my original object of desire was the storyboard, and trying to find my path up through the object catalog lead me to the approach described above.
So here's my original intention that I'm still struggling with:
I want to turn things "back to normal", i.e. get rid of this obnoxious storyboard and snapshot's storyboard-associativity. So far, i figured out, that presentations, that have been created with older versions of inventor, and are opened in Inventor 2020+ are converted into Snaphots whose StoryboardAssociative flag is set to "false".
I haven't yet found a button in the GUI which breaks this associativity from newly created Presentations/Snapshots. But fortunately you can do it using the API:

So, after done so, you end up with some schizphrenic browser that shows different things, wether the Snapshot with broken associativity is activated for editing or not:

So, after breaking the chain to that $%&§!-Storyboard, i'd like to get rid of it. Turn's out, I can't, but at least i'd like to flush it's content down the toilet to prevent me or other's to accidentially try to alter the wrong explosion paths.
Inside the GUI I can mark the Browsernodes and say "delete", and after that I am where I want to be: Orphaned, empty Storyboard, and free explosion paths in my now unbound Snapshot:

->
&

-> I'm happy! 🙂
As this clicking-orgy is tedious and needs to be explained to everybody multiple times, i'd like to fully automate it.
Turns out, when I grab my PresentationsTweaks via their browsernode to call their "delete" method, I end up with an empty browser, but a still populated Storyboard:

So, how do i get rid of the storyboard's content? That's why i ended up trying to get hold of the storyboard-object by going through a horse's a55 to get to its mouth, to find somthing i can flush there, but apparently, the API is as messed up as the GUI. At least, there is nothing left, that i could flush:
