Can my new wife, waiting for green card, get insurance? She has cancer.

She is a 55 year old Filipina. Just found out she has Endometrial cancer. Has no insurance, but we just married in January. My previous wife and I sponsored her to get her green card for 6 years, until she passed away. Reapplied for her green card and is now in process, but it may take 6 or more months to get it. I am 56 and have medicare because of disability. I cannot put new wife on my existing policy. Can I change to a different companies policy with Medicare and put my new wife on that policy?