Wesker had been observing the chaos from a nearby rooftop. He had dispatched Jill earlier that day, testing her, seeing just how far she could be pushed before her ability to resist the device on her chest could overpower the drug. The drug he used to control her was not found in this world, and even the closest copy he could make using Pfizer's materials wasn't perfect; eventually, her body would naturally build up a tolerance to the drug, and she would be beyond his control. Now, he was simply testing her; both for his own amusement, and to assess any permanent side-effects of the mind control formula.
The would-be God watched Jill dive into a building. He knew the sound of the animal inside; a tiger, most likely escaped from the Central Park zoo. A starving animal could find a way out of just about anything, determined to sate their hunger in any way it could. Assuming it was eating zombies, chances are, it was mostly likely infected itself from consuming a zombie's flesh. Whether or not the virus could mutate to affect non-humans would certainly be interesting to find out.
Wesker seemingly vanished into thin air, and reappeared on another rooftop, watching Jill. How would she handle this? She was most likely armed, and all it took to down a feral animal was one well-placed bullet. Would Jill collect a skin sample for Wesker to study later? Would she even remember? Or was she conscious enough under the influence of the drug to resist going the extra mile?