You are looking for a "legal" way to make a seller, from a deal you cancelled, change the information on his home's listing?
I don't really see what you can do.
You already reached out to the Broker (I assume you contacted the Broker, not just the agent - if not, and you want to pursue this, then call the Broker).
You, however, are out of the deal, and really have no actionable optionsat this point (in my non-legal opinion).
Not sure why there was "miscalculation" - perhaps the sellers are disputing that claim.
Move on and find a new home.
Best wishes...and happy holiday!