Well, no, I'm not sure either; none of us are. It all depends on what Sidious shared with Maul at this point. What the episode confirms is that he shared more with Maul than we were aware of up to that point, based strictly on what The Wrath of Darth Maul told us. What is in dispute is how far that sharing went. But the Plagueis novel (amazingly, on page 327, LOL!) does give us a very good idea of what Sidious himself knew leading up to the day of Maul's death. As of the events of TPM, and for as much as two months prior, Sidious was already aware of the following aspects of the Grand Plan, jointly decided on by him and Plagueis: 1.) That the Sith will engineer a war in which both sides will have to be managed. 2.) That on the one side will be the Republic, defended by the Jedi Order, which will be maneuvered into being placed at the head of an army of cloned human soldiers created by the Kaminoans. 3.) That on the other side will be a loose alliance of the Sith?s corporate allies and the disenfranchised systems of the Rim, led by people the Sith can control and supported by an army of battle droids. 4.) That neither side will secure a quick victory; instead, a drawn-out conflict will leave the galaxy exhausted and ready to embrace a new order. 5.) That at the end of a long war, with victory apparently in sight, the clone army will launch a surprise attack on all combat-capable Jedi in the field, killing the majority of them instananeously and all at once. That's quite a lot, and very much what actually happened, even if only described in broad strokes, as it would be at this point. So we do know without question that Sidious himself knew this much. If indeed Maul was convinced that he was meant to have some greater role in this war (and we have to assume that Talzin's green-magic restored his full sanity - or what passes for that - or he would still be a babbling spider, so he can't have been delusional when he said it), we have to assume he knew some part of what Sidious knew. It would be perfectly in character for Sidious to leave certain things unsaid, of course; that's one of the reasons we love him. But would Maul say what he said if he knew nothing at all about that plan, beyond the fact that there was a general intent to sow chaos? The potential is there for him to have known much more than that; as you say, we have yet to absolutely confirm that he knew everything I listed above, but his phrasing leaves the possibility open.