I was working for an Indian IT company back then. According to my colleague, they offered really good health insurance (I never pay attention to such things, so don't know how good it was compared to others). I got a dental cleaning and wisdom tooth removal done once, and had to pay $2200 from my pocket since insurance didn't cover those. The dentist told me before the treatment itself, and so wasn't a surprise. Another time, I ended up having to go to a hospital couple of times for an issue. Total bill was around $20k. I had to pay only $50 from my pocket. After I came back to India, I got another letter in my US address from the hospital (nearly 1.5 years after the hospital visit). I suspect it could be another bill. I knew about the letter because I still get the USPS informed delivery email alerts!

My friend also worked for an Indian company. His wife had a delivery and there were complications. I am not sure what really happened. He one day called me and told me to have some money ready (around $2-3k) in case he needs to borrow. He said he had to pay a lot of money from his pocket, and that he reached the maximum limit (after which insurance pays everything?). He was in US for around 1 year, and left soon after because the project was over or ramped down. Just before he left, he got another bill for $3 or $4k and he said he is letting it go to collections. After he came back to India, I asked him about it and he said it was taken care off (didn't say if insurance paid or he paid or he ignored it).