Not really, late victory mean just that the A-H had bought a couple of very troubled life; the war has been too much, too blood and tresure spent not considering even the fact that the entire military and political leaderships has lost most of their credibility and legitimancy and the post-war political and economical problem will add to the pre-war ones and the nation it's not equipped to survive it.
By 1918 the Hapsburg Empire it's a whole owned subsidiary of the German Empire, so there is no incentive in remaining attached at a troubled corpse unless Berlin decide to prop up for her reason and post-war they will have their own political and economic problem.
But whatever problems Germany has, she's hardly going to let the power which covers her south-eastern flank just dissolve into a bunch of petty states, many of which might be hostile to her. Even the Social Democrats aren't likely to advocate that.
Secession or revolution during wartime it's not a simple thing, you need a total collapse of the previous authority or an extremely dire military/social/economic situation like in Russia, the real problem come in peacetime, when there is no pressure from an external enemy and in general people want to know why they have sacrificed so much for so little (frankly after this kind of war, none will be satisfied from what obtained at the peace table...as it's basically impossible).
Winning the war it's the almost trivial thing in this scenario, the real hard work for the CP (in a late war victory scenario) will be winning the peace.
Sure, the place will certainly be a mess, but there's still the question of who secedes and where do they go.
The Czechs can't. They are all but surrounded by areas of German population, and have a massive German minority within. A revolt there would be lucky to last a week. And even if for some reason the Habsburgs were unable to deal with it by themselves, it would cost Germany nothing to station a few of her divisions in Bohemia instead of Saxony.
The Hungarians would probably like to secede, but they'd be taking a chance doing it without Germany's approval. The Germans have a bone to pick with them over the Magyarisation policies imposed on their German minority, and in a Europe where Deutschland really is "uber alles" may decide to do something about it. And if Hungary insists on breaking up the Dual Monarchy, the Germans might decide to subdivide Hungary itself. Warum nicht? She could all too easily end up suffering a "Treaty of Trianon" imposed from Berlin instead of Paris.[1]
That leaves the Croats, but they can probably be satisfied by a degree of internal self-rule, comparable to what Hungary already has. The Magyars will no doubt scream blue murder, but if they try to secede, they most likely lose Croatia anyway, so they can't really
do very much. And if the Monarchy holds on to Bohemia, Hungary and Croatia that reduces the problem to one or two outlying provinces, which is probably manageable.
The long run, of course, is harder to predict, but I doubt if collapse would be as imminent as all that.
[1] They also have some gripes about Hungary's wartime behaviour. I forget exactly where I read it, but istr an incident in 1918 where a shipment of grain
en route to Germany was seized by a Hungarian mob, with the local authorities apparently not making much effort to prevent it. Ludendorff, iirc, was spitting rivets and talked about sending in troops, but refrained because he couldn't spare any from the Front. So Hungary may find that it has few friends in post-victory Berlin.