Medicare 是secondary，你雇主的blue cross是primary

Medicare网站上说的。你还是去和医院官方核实一下吧，护士随便说的不一定可靠。

I’m 65 or older and have group health plan coverage based on my or my spouse’s current employment status 
• If the employer has 20 or more employees, then the group health plan pays first, and Medicare pays second .
https://www.medicare.gov/sites/default/files/2021-10/02179-Medicare-and-other-health-benefits-your-guide-to-who-pays-first.pdf