RDF is dead. Thats not to say an airport or a handling agent hasn't dropped their keks for any new business. Joe's claim of "multi million" agreements is absurd, for Zoom or anyone else, RDF or not. Such claims require evidence, please.
EDI might well have cut a deal to bring ACR (already heard them called Air Canada Rogue!!!!) to the local, but as I keep saying, its the airlines/the market who decide where to operate, not the airport operators.
Having said all that, theres nothing to say ACR prices won't drop, or TSC prices won't increase - a snapshot today is no evidence of overall strategy. ACR might have a January Sale! Book Lufty to DUS today ex GLA for £98 return. Look again after Christmas and it will be at least £150. KLM are similar from the UK, there are regular offers from time to time.