Yuka successfully signed a blood contract with Mount Myoboku at the end of the year, gaining the ability to summon many of Mount Myoboku's toads.
However, she was still young and her Chakra reserves were not large. (She could acquire more Chakra through Xiaolan, but this would easily reveal clues, so Yuka had not exposed this matter.) The only ones she could summon were Gamakichi and Gamatatsu, but both toads were still children, and their abilities were far inferior to big toads like Uncle Gamabunta. Even if she summoned them out...
In Uncle Gamabunta's words: "You two really are of one heart and mind, even getting beaten up together!"
Chapter 147