Health Insurance Cancelled without Notice

I have a friend used to work at Robinson's May and when it merged with Macy's in 2005 her Anthem Blue Cross Health Insurance was stopped because she lost benefits. The problem is that she was never notified that her health insurance was stopped. For this reason, she went in for a surgery that she had scheduled expecting her insurance to cover it. There was even a confirmation letter from the insurance that everything was on the go and that it would be covered. Some time after going through with the surgery she was then notified that the payment was reversed and that she was personally now responsible for the $60,000 dollar visit to the hospital. Had she known that she would be responsible for paying this she would not have gone through with the hospital visit. One thing to note is that I believe that Robinson's May did not notify the Blue Cross health insurance that her benefits had been terminated until after her surgery had already taken place. Therefore, I believe that Blue Cross wasn't notified of the two companies merging until after the surgery had taken place. Would it therefore be Macy's fault for not informing her that they had canceled her health insurance? Also, I believe that they merged back in 2005. Does the fact that it happened so long ago have any affect?

My question is: are there any laws pertaining to the health insurance or Robinson's May being legally obligated to notify my friend that her health insurance had been stopped. If she had known all of this would have been avoided. I believe her health insurance was covered by ERISA as well. I looked at ERISA 29 USC 1341 but I am not sure if this pertains to this situation. This all took place in California. Any help is much appreciated. Feel free to email me at garciask8r@aol.com.