75 year old dad has multiple myeloma (cancer) and in SNF. Anyone know why they won't cover radiation and chemo?

My dad has injuries related to his bone cancer and is in a SNF receiving PT with hopes of gaining enough mobility to go home and be able to toilet himself and do other functions of daily living. My mom is 73 and lives at home and could help with some care, but it would be too much for her in his current state of disability. Meanwhile, dad will need radiation and chemo while he is in the SNF and we've been told that the chemo will not be covered while he is in a SNF. Anyone know what that's all about? Medicare.gov says it is covered and that there is a procedure called consolidated billing that needs to be followed. Not sure if the oncology group says it's not covered because they have to submit through the SNF or the SNF won't comply with the oncologist? Prior to requiring care in a SNF, all cancer treatments were covered by Medicare and supplemental insurance.