In her 'eureka moment' during her conversation with Angel, Katara had remembered that Dar was in the hotel. She had also remembered, shortly afterward, that he likely had yet to figure out how to use a computer. Which meant that there was a good chance he might not even know what was going on. Or, worse yet, have tried to befriend one of the snakes and gotten himself bitten in the process.
It was that last thought that made the waterbender decide that finding Dar was her top priority. She'd keep freezing the pipes as she went, of course, but she had to make sure the Beastmaster was okay and, if he was, enlist his help in stopping the attack.
Making her way to his room, Katara kept an eye out for any snakes. She encountered one as she reached the top of the stairs but a quick jerk of her hand had the small, razor-sharp icycles that had formed on her fingertips flying off and decapitating the snake instantly. Stepping over it's still-writhing body, she froze another snake on the spot and sent another crashing out the window at the end of the hall courtesy of a large wave of water.
Finally, another snake (and another beheading) later, she was finally at his door. "Dar!" she called through the wood. "Are you in there?"