If you have an expectation that every event in history is accompanied by the instigators writing/saying "Let's all go do an X" (where X might be "coup" or "revolution" or whatever), you're going to be disappointed.
Most often, it's only historical hindsight that forms the narrative in which "X said Y which led to Z".
If you're somewhat sympathetic towards Trump, then likely only utterly unambiguous language - "So listen up everyone, I want you, in fact I order you, to go to the Capitol, get inside, prevent the certification from taking place, by any means necessary, including violence" - would convince you that he had incited a coup (and perhaps not even that).
Out in the real world, few people speak in such unambiguous ways even if their goals are clear. That's why we often need trials to establish whether or not certain language had intent A or intent B, because the language used was not unambiguous (often deliberately so).