This cage isn't cheap but it's great for a robo and the Zoozone could sit on top. I used this for our robo. It's basically the same as the Hamster Heaven but with narrow bar spacing - no door on top and the big front opening door is great for interaction with a robo. You need to take the grid shelf out though. I just added a wheel, a labyrinth house and a shelf and floor toys. Anything smaller than the Zoozone 1 would be too small.
Apart from the narrow bar spacing it is better built and much lower than the Alaska so avoids fall risks.
https://www.amazon.co.uk/Savic-Micke.../dp/B003QRMBG0