What would the non rent violation be? Owning a turkey fryer? Plus the OP said he no longer uses propane, so he "complies". So as far as a cure or quit notice is concerned, he fulfilled the obligations of the "cure".
Without seeing the rental application, I'm not sure. Personally, I'm not a property lawyer and I sure as hell stay far away from Wisconsin, I'm just noticing that Wisconsin's laws regarding eviction are harsh.