Sorry my comment was a bit cryptic 😊

I have stayed in the past for a London base - trains from East Croydon station head for both Victoria and London Bridge. I also stayed twice to connect to the Eurostar via the direct train to London St Pancras International station. As you say the mid/north-station footbridge comes out nearly opposite the hotel entrance. Oyster card readers and lifts are available from this exit.

I believe the last stay it was 1/4 of the price compared with the Hiltons near Eurostar in Euston or Islington and the train journey is only 30 minutes!!