Dooku toys with refusing. He really does consider declining the offer. But...he's already stepped in the bantha poodoo, so he decides to ask for someone to help him not step in anymore. "Would you like me to introduce you to him?"

To be frank, Obi-Wan Kenobi was his first choice for any help, if just because Obi-Wan and Bonzo knew eachother decently well...and because Obi-Wan had dealt with his own difficult case, too.