With more complexity, the system might be less likely to go to extinction since the competition could be alleviated by resource partitioning. However, if this change made the "loser" in Fig. 56.9 more preferable as prey, it might make extinction even more likely.
Work Step by Step
These kind of "what would happen questions" are often hard to answer definitively without hard numbers. The best answer is to look for reasons why either direction might be taken.