Aetna rep gave me incorrect coverage information and now claim and appeal have been declined (CA, USA)

Hi there, I had an EEG done at an out of network provider. Before I had my appointment I called my insurance (Aetna) re: coverage and they told me both these CPT codes would be at least partially covered and that I did not need pre-auth for coverage.

EEG Analysis: 95957

EEG Recording: 95953

Based on this info from the Aetna rep, I went ahead and had this $750 appointment and filed an out of network claim to Aetna. They denied this claim saying that these CPT codes were deemed experimental. I then found out from speaking to a second Aetna rep that coverage also depends on the exact ICD10 diagnosis code the provider bills with the CPT codes. I had no idea and the Aetna rep I spoke originally did not mention this. I filed an appeal with Aetna with a call date asking them to listen to the call recording and explained I didn’t think I should be held responsible for an agent’s misinformation; I wouldn’t have had the service done if I was told those two CPT codes were going to be deemed experimental.

Is there anything I can do now? To say this is annoying is a understatement! Thank you very much