Follow DJI instuctions to the letter; wait for the label, follow precise instructions from DJI. You'll send the whole kit back and they will send you a brand new or refurbished complete drone kit back.
Another thing. get to know your the limitations of your drone and equipment. As much as they have obstacle avoidance, it has its limitations; it can never emulate a pet bird following you through a forest or trees whatever.
Forget about applying for the drone permit. Like you said it’s next to impossible. I just flew my mini 4P. Of course not doing it out in the open. The Mini 4P is pretty stealthy due to its quietness and small size.
I can tell from your video, some things have modernized in Istanbul; there was no metro back then. During our week long stay, we didn't do very much except relax, eat and drink beer. The remaining drive through rest of Turkey, Iran...