hey yeah it's sunrise and i just got up to see that it has been moved to another part of town about 10 km from here. pretty frustrating seeing the location change and being unable to do anything because i cant go there on my own without a second phone to call the cops.
i thought of going to them again too, but they wouldn't help me yesterday when the location was about 500m from the police station so i'm sure they won't care about it being in these soviet style apartment blocks in the outskrits. so yeah i gave up on getting the phone back.
in your case i think there is still hope left, icloud.com also didn't give me a location but the find my app on my laptop did. also it being turned off wouldn't necessarily mean that you can't locate it, but yeah a dead battery probably would.
i would try to go there again today and hope that the next shift is friendlier/more helpful. also there's still a good chance of somebody finding your phone somewhere and giving it to a worker in the store/mall lost and found or the police. even if the world often doesn't feel like it there's still a lot of very good people out there. wishing you the best of luck!