My question involves collection proceedings in the State of: Colorado

Background:

Minor child had a dental procedure approx 3/2012. The provider is in-network for Cigna.

#1 - Provider states we never provided the insurance information to them to bill; though insurance shows claims both before and after provider in question rendered services.

#2 - Provider sent us to collections that showed on the credit during a mortgage application - which stopped the process.

#3 - The provider will not respond to questions from the guarantor via email and assigns incompetent staff to answer questions which they cannot do. This has happened three times already.

#4 - The collections agency now seeks bill + $300~ stating they have already demanded payment to the rental we have now, albeit the date they provide as having sent this to us is before the move-in date to the current location. No demand was received at the previous address otherwise it would have been paid.

Issue: obvious we're trying to get a mortgage, but are hamstrung due to the non-responsive provider and the collections will not negotiate in any capacity and the only information they've sent was the ledger provided them from the provider themselves. This had no dates or service, procedures, payments etc..

So, my question is: #1 how is the collection agency allowed to bill substantially in excess of an amount of a bill for which we've never received? This seems to have an element of extortion tied to it...

The insurance has already said that timely filing has expired, so they will deny the claim, but we gave the provider that info. Can we force this into court and/or would this be helpful at all? I feel like we're being extorted due to their lack of administrative competency due to filing and are basically stuck.

We have sent letter after letter to the provider asking to pay this, but they won't respond to us, but are also not referring us to the collections agency, nor is the agency cooperating to any extent.

Thanks in advance!