So the voting machines have WIFI capability, but it is usually off.. isn’t something the typical admin can turn on (because it is grayed out), but there may be a super admin method of enabling wifi.
The whistleblower could elaborate on which services would be available if wifi was turned on: SSH, database, web, etc.
Now if the router logs were saved, and you could show that a wireless device with a MAC ID matching a voting machine logged onto the WIFI.. that might be interesting.. More interesting if the database were accessible via WIFI.
It is something the typical admin can turn on, that's why they're admins. A user can turn it on as well if the BIOS settings are not password protected. You just have to make the change, save and exit and it will be enabled on the next reboot. You (or an admin) don't have to password protect the BIOS settings if you don't want to - it's just another option of many in the BIOS.