If you are able to ssh into the RPI Zero2w that is in the hub, as the pi user then you "should" have the permissions needed.
What tool are you using to ssh into the RPI Zero?    the command should be ssh pi@IPAddressOFSmartHUB. the use the password raspberry
If you do not specify the pi@ part it will try to have you ssh in to the RPI Zero as the user of your host computer.  It may ask you to accept ssh key for the pi user if you have not already done so.

Once you get logged in you can type whoami to valdate you are the pi user if you want. You can type pwd to see what directory you are in.. It should be the home folder for the pi user. To run a command as with root privileges you would use sudo COMMAND... such as sudo nano config.html  (nano being the text editor.)