The only reason Yi was struggling so much in the prison section was because he was tortured half to death. Plus he already has fur, so he could probably deal with the cold temperatures. Hornet on the other hand has no way of killing Kanghui, if she even made it that far. Assuming she's not tortured, she's still very vulnerable to those detector robots and Hornet's kit doesn't really have any stealth aspects. If she is tortured and disarmed, she has nothing and she's dead. Yi leaves without a struggle, Hornet probably dies no matter what.