Tivo Mini (RCN) and no ethernet or coax connection

I have an RCN Tivo T6 home bundle. The main internet signal is coming in to my Apple Airport Extreme. I have two Tivo Minis in the house in two other rooms. They are connected via coax and a MoCa connection. (that is about as far as my technical knowledge goes.)

I have a roof deck and would like to get TV and TIVO up there. There is electricity but no coax cable or Ethernet connection up there, and getting wiring for either is out of the question. There is a strong WiFi signal as the deck is just above where the Airport Extreme is.

Here is the question....can I get an Apple Airport Express and plug that in on the deck - then plug another Tivo Mino using the Ethernet port on the Airport Express, and connect the Mini to the TV up on the deck. Will that allow me to watch TV and use the TIVO outside?

I would like to have some sort of solution before RCN comes out, as they often do not know what they are doing.

Thanks!!!