Employment Law Questions? Ask an Employment Lawyer.
I really would encourage you to retain an attorney here. While you can make a complaint with the OK Dept. of Insurance (here: http://www.ok.gov/oid/Consumers/Consumer_Assistance/File_a_Complaint.html), in my experience if you are in a dispute with the carrier over scope of coverage, filing a complaint with the state can often complicate (rather than facilitate) a resolution if you have to get counsel involved later.
(I know that customers don't come here to be told "go hire a lawyer" so I want to explain why I am giving you the advice). Your dispute with the carrier has a good chance of being resolved in your favor (you tendered the requested premium prior to the loss, the tender should act as an "acceptance" of their "offer" and thereby created a binding "contract" (all the elements are met for the policy to be binding).
I would hate for you to lose a decent shot at coverage by trying to save a few bucks on counsel. Hiring a civil litigation attorney early in the matter is probably your best option to get your coverage decision resolved favorably and quickly.
You can find local attorneys using the State and local Bar Association directories, or private directories such as www.AVVO.com; www.FindLaw.com; or www.Martindale.com (I personally find www.AVVO.com to be the most user friendly).