I cant see how the loss of analogue would stop you getting Sky in that room as I assume all the cables are still as they were before analogue went.
The fact that an analoguie TV signal is no longer being sent out should not affect your setup.
Do you know what type of cable is connecting the Sky box to your TV and what "sockets" they are plugged in to (Scart or whatever).
Have you changed any of the cable setup at either end since the analogue switch off?
Have you perhaps removed a video recorder from the setup, or perhaps switched it off since the analogue switch off? (maybe the Sky signal was going THROUGH the video recorder).
It does seem rather strange.