Fighting anesthesiologist costs

I had surgery on 1/1/2023 at a major in-network hospital (for Cigna) in Virginia. It required anesthesiology – I wasn’t informed that the anesthesiologist was out of network. In fact, the anesthesiologist group was kicked out of Cigna’s network the exact same day of my surgery (1/1/2023). Total costs were $7000; I had the claim reprocessed through Cigna and I’m left with about $1000 from the anesthesiologist group – I think Cigna’s calling it what I have to pay for my out-of-network deductible.

I’ve completely reached my in-network deductible, but not my out-of-network because I do my research beforehand. Except, in this case, when it happened day of (i was in the hospital starting 4AM 1/1/2023 and was not in the right mind to research anything).

Is there anything I can do? If so, who should i be reaching out to? I reached out to Cigna and the rep said they’ll put it through to review under the No Surprises Act/balance billing protection. But wasn’t sure if that was the right thing to do first and wanted to check in case I’m missing anything.

Thank you!