BSSID vs MAC address?

The MAC address is the access point (AP) address.

Each AP can support up to 16 SSIDs (Service Set ID). Each of these SSIDs has their own MAC address derived from the AP MAC address.

For more information and to see how the BSSID derived from the MAC address please see: https://community.arubanetworks.com/t5/Controller-Based-WLANs/How-is-the-BSSID-derived-from-the-Access-Point-ethernet-MAC/ta-p/176290

I hope this answers the question for the future viewer.

The MAC address identifies a piece of hardware. The hub has a MAC address, and so does your network card which is connecting to it. The former is also the BSSID.

getConnectionInfo will be returning your MAC address as "MAC address", and the hub's MAC address as "BSSID".