I called and spoke with them this morning and I am glad I did, extremely helpful.Call and talk to ADGU - the current set up for the drawer has space behind the fridge for a power station; however, I spoke to them last week and they said they are changing the fridge drawer set up and it's now not an up charge because it doesn't have a drawer underneath the fridge. I don't know if that means there is no longer space for the battery behind the fridge but they are quick to respond and they will show you videos of the two different fridge drawers.
As of now, they are only offering the CD30 fridge. The other fridge was a one off or something along those lines, the CD30 is the fridge they are offering.
Yes, you can mount some power stations behind the fridge, the space is roughly 17"Wx10"Hx12"D. He specifically mentioned the EcoFlow Delta 3 2200W unit is what he used so this is what I am going to go with. It should power the fridge for 2-3 days and they have the hardwired alternator charging option as well.
As for the change in design with the fridge. Currently, if you get the fridge on the passenger side it is mounted in the table slide and can be slid out completely giving you access to the power station, the drivers side is not like this due to it this side being one inch narrower. This will be phased out in the near future.