Hospital billed emergency surgery as outpatient, now indemnity plan won’t pay, any recourse?

Background: A couple months ago I went to the ER with abdominal pain. I was eventually seen in the ER where they determined I needed emergency surgery. (Further background: I had already been to the ER recently for the same condition and they referred me to an outpatient surgery consult in about a week, but the condition worsened and I didn’t even make it to that appointment). I waited for a bed in the ER and was eventually moved into a pre-op area of the hospital. I spent the night there and had the surgery the next day which took several hours. I was then moved to a post-op area where I spent another night. The next day I was able to eat again so I had a meal and at some point in the middle of the day was discharged.

I have a hospital indemnity plan through my insurance which theoretically pays out if you have an emergency and are admitted to the hospital. Come to find out that the hospital never technically admitted me and billed the whole ordeal as outpatient surgery, even though I came in through the ER. So therefore, I got a letter yesterday from my indemnity plan saying “it looks like you weren’t in the hospital since there was no admission nor room and board charges, so we don’t have to pay anything”.

At this point, it was several months ago and I’ve already paid most of my copays. I was just waiting on the indemnity payout to finish off the rest.

Do I have any recourse here to say, no I was definitely super in the hospital for almost three days, wtf? Or am I just SOL and at the mercy of whoever decided to code the procedures?