no need 破產
even you do not pay, after 3 years , the debt be forgeted. Most bank can allow you have medical debt stay there. It will affect your credit score and intreast rate when you apply for house loan. But it is much less than chpt 7.
I suggest that you pay. It is not worth claim chpy 7 for $20k if you plan stay in US. If you plan go back to China. Does not matter also.
So, any way, no need to file chpt 7 .