Aside from messing with House, Vogler canceled the procedure to ensure the drug trial that House was trying to get her into was not affected by the high risk of the female patient causing a negative result in the drug trial.
House: So she kicks off, his numbers look bad
Vogler: The numbers look bad, the study looks bad
House: Which would cost you money
Vogler: Yeah, and keep a life-saving protocol off the market
House: One person, one blip in the data
.....
Vogler: One person should never endanger the lives of 1000's
Source: House M.D., Season 1 Episode 18, around 29m30s
If the C-Section had gone ahead (a must-do before the experimental drug could be administered) THEN she were rejected access to the trial, I'd say that would leave the hospital more open to liability - tricking her into a C-Section she never really wanted in the first place so the doctors could do as they please.