bill as a network when not one?

Just checking to see if this is a normal thing that some doctors do and if this is legal and how insurance companies deal with this. I have an appoint with a surgeon who is not in my network and when I went to check on that his office manger told me that he bills as if he were in network.
I got a call from United Health Care (case managment nurse working with their obesity dept) she told me that I needed to think about turning my paper work in and to find a surgeon. I have checked with 3 names she gave me but they will not do my revision and I want to go with someone who has experience but he and the hospital is out of network.  Also if the dr does his billing that way does the hospital usually do to. I forgot to ask her that.
I want to make sure I know that this is something that takes place and that when I call United Health Care and tell her I have choosen to go out of network and what they said that she does not bring the hammer down so to speak.

#1 - It doesn't matter how the surgeon or doctor or hospital bills the insurance company; the insurance company KNOWS who is in or out of network and will pay accordingly. It has nothing to do with how they are billed.

#2 - If there is no surgeon who can do what you need who is IN network, the insurance company may cover someone out of network as if they were in network. Get specifics on what revision procedure(s) you need specifically from a qualified surgeon, even if out of network, and then go to insurance and show that the in network surgeons cannot do what you need.

it is possible the first surgeon means he will only bill the in network amount that he knows the insurance will pay instead of his full fee. it shouldn't matter to the insurance as long as they are only paying the innetwork benifit
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