There is always an amount “billed” to insurance companies which is strictly imaginary. There is this billed rate, the negotiated rate per insurance provider, and a cash rate.
An equally imaginary number that gets hauled out during debates so that health care providers can pretend that insurance companies are the ones responsible for price inflation. If you actually try to obtain the cash rate, they'll give you a 2% "lol nice try" discount off the billed rate.
No, there’s just a base rate that nobody pays used as a negotiation tactic that’s still published on bills for whatever reason, you can see what your insurance provider actually pays as well.