Actually hold on I think you might be the person that could do this justice:
De-aging incident. Was intended for someone on the Republic's side, but backfired and hit Dooku instead. He's now approximately eight years old, and incidentally in the custody of [insert disaster lineage member here]. He remembers absolutely nothing past the age he appears. The battle droids still listen to him, because he hasn't been removed from position as the CIS Supreme Commander, so when someone suggests he tell the droids to stand down, they do, which like... they do, but nobody knows what to do with Initiate-age Countling Dooku.
Really, there’s really only one thing that’s fundamental to Dooku, no matter the characterization: his competence.
He is the definition of ‘knows what he’s doing’ because he doesn’t really do things he’s not good at, and he’s structured his life so he doesn’t have to. He’s highly accomplished and extremely clever, and both of those make him very, very good at getting shit done.
Unfortunately, a highly accomplished eight year old is still an eight year old, no matter how clever and good at chess they are for their age. A child genius is still a child, and children, as it comes, lack a good deal of experience with—well, most things.
So if you toss eight year old Dooku into the middle of a war that he helped engineer, make him commander in chief of an entire side of that war, and tell him he can do whatever he wants, he’s not exactly going to be able to handle anything.
In a matter of hours, the Separatist Army crumbles. (It would have crumbled a lot faster if Dooku weren’t actually trying to manage things, but hey—he’s a pretty smart eight year old. He’s at least grasped the idea that he shouldn’t do anything too drastic until he knows what’s going on, and so he issues an order for everyone to just… keep doing what they’re doing. Occupied planets remain occupied, which works out fine. Battles, on the other hand, are lost where they shouldn’t be lost and won where they shouldn’t be won, since, you know, Dooku was the one who strategically pulled victories to ensure a drawn out war-effort.)
The Council figures out that something is happening fairly quickly, and since they’re sort of a one-trick pony, they do what they do best: throw Obi-Wan and Anakin at it.
Obi-Wan and Anakin show up on Serenno, ready to violently negotiate (Obi-Wan) and/or violently murder (Anakin).
Instead of finding Count Dooku, military genius, richest man in the galaxy, and evil old bitch, they find Initiate Yan, who would really, really like a space capri sun right about now.
Jedi! Yan thinks. I’m saved!
What the fuck! Obi-Wan and Anakin think. This is fucking insane!
So begins Operation 'Bring Kid Dooku Back to the Temple Without Informing Him of the Vast Amounts of Horrible Shit His Future Self Did While Also Not Dying to Ventress.’ It is not, as things go, a rousing success. In fact, it’s pretty close to the opposite.