I'm not sure my opinion is really interesting as this is, by far, beyond my competency scope. However I've tried multiple connections after having successfully loaded the .cpp program in arduino to ESP32.connections to esp32 network are not systematic and most of the time, the network is not visible. when connected the webpage opens, but I never succeeded having a shoot with G7x, G9xii nor M200, (this last one being also CCAPI compliant).I would be happy to perform any tests if needed, alghough I do not always understand what I'm doing. After years using CHDK/SDM while camera had video out features, i'm currently using a esp32+webpage with ccapi camera.I would be really happy to get a liveview feed and shooting option for cameras like G9x2.
Ok, so try to do things in this order:
After you uploaded the code to the ESP32, go with your phone/laptop to the newly created hotspot, then Config SSID, and put your wifi network info there, so that it logs in to your wifi network. Then restart the ESP32 if needed.
Connect from your PC to the esp32 (via your network, not via hotspot)
Make sure the camera is connected to your router, and in the same network as your PC (not as hotspot). Then get the IP of the camera (check the router clients page) and then go to Config Camera on the esp32 webpage. Put there the camera IP, and click Set. Make sure the camera is in the Connecting to phone mode, then click the Canon PTP Shoot.
If it still doesn't work, please look at the log of the ESP32, see what it outputs by serial. Are you using Arduino or Platformio?