Red Queen was in the learning phase of her evolution because she was now learning how to adapt to the thought process and functioning of the Organics. It was an entirely new experience for the Super Advanced Hyper Artificial Intelligence, and it was something about which she was genuinely interested.
So, she chose both Zehal and Jenaiel as her subjects of observation because she found the two women rather intriguing. Either for their conflicting personalities or for their personal abilities.
Neither of them was weak; they were strong-headed, and most of the time, they acted rather irrationally and without any semblance of reason. Still, she continued her observations, as they could be helpful for her evolution into a fully sentient thinking machine in the near future.
