I can't tell if you're claiming that this bill is from the air ambulance, or from the other ambulance that came to the scene. If it's the other ambulance, your provision of insurance information to the air ambulance wouldn't automatically translate into their having received your insurance information.

You're stating that nobody is presently contacting you about the bill, and it's not on your credit report, but that you want to contact the ambulance company to try to negotiate the bill and a repayment plan?