According to today's press release from Skate Canada, Ralph/Hill are going to skate at NRW.
The TES minimums for Worlds can be met in the season before or prior season at ISU events and qualifying Senior B's, i.e, ones where there are enough skaters, judges, tech people from enough countries in the discipline, which is most of them. Orford/Williams have not made the TES SD minimum of 28 last season or so far this season. Were they to qualify for the Olympics or 4C's, they'd have a chance to make the score at that event, should they not make it at TEB. Barring injury or disaster, with the Canadians highly unlikely -- or, possibly, on the record -- not sending the Olympic team to 4C's, they should be Top 6 and earn a berth at least at 4C's.
[ETA: O/W had qualified for Worlds last season, based on their SD TES of 30.64 at 2012 Jr. Worlds, but the 2011-12 season scores dropped off for qualifying this season.]
The Canadian 4C's team should be quite strong this year.