There is surprise there, and Dooku has been around more than enough politicians to have some control over his own reactions, especially so as there's a mention of a confederate ship. And truly, knowing the name of the faction is a beginning. Even when he tries to remember anything he could have read about current conflicts of this scale, no matter how far from Coruscant, and can come up with absolutely nothing that might fit.
Then there comes the question, and Dooku's first thought is of his father: Count Gora of Serenno. And of course, courtesy of his recent landing on this planet, he doesn't have all the information.
"Yes." He replies, tone steady. "And neither the ruling Count of Serenno nor I are particularly pleased about it." He adds, before speaking again. "Nevertheless, I must thank you, and your troops, for your timely rescue." And then, "Is the Council aware of this engagement already?"
Which is very much fishing for information, but he's injured enough to not care just yet.