Yes, you can.
Here's what you need to do to see the Keezel's MAC address:
- while connected to your Keezel WiFi, go to keezel/ in your browser
- click on the "hamburger menu" in the top-right corner of the page - the 3 horizontal lines next to the Keezel's battery indicator
- click on About from the menu
- you will see your Keezel's firmware version, app version, and MAC address