Back on topic 🤨
I think that through huge amounts of difficulty Dooku would eventually lose. In the ROTS novel (non-canon i know, but people like to use non-canon info and put down non-canon stuff) he was getting tired because Obi-Wan and Anakin were using Ataru fancy jumps while he was attempting to toy with them. If Dooku tries toying with the three Jedi, he will quickly lose his energy and lose. However, if he doesnt, he would probably kill Ki-Adi and possibly Kit, but Obi-Wan may survive.
This is very difficult to decide, because in ROTS, Dooku tosses Obi-Wan like a toy, and if he does the same (providing he can seperate all three Jedi to have the time to toss Obi-Wan, which is unlikely) he would be able to take on Ki-Adi and Kit