I just figured it out partially.
It is because this feature "delete later"
The points are only deducted when I delete the topic/post permanently in modCP.
Here are the exports anyways.
Any content deleted = Without conditions, works only after permanent deletion
Any content deleted C = Doesn't work, generate the error quoted above (invalid container), after permanent deletion
Topic deleted = Works after permanent deletion
It is now clear that I have to disable that feature for now, but I don't want to, plzzzz don't make mee
Make it work instead, just like hidden content