Need help with Medicare coverage of inpatient rehabilitation for a stroke. Any ideas?

Have you talked to the discharge department? They should have the information you need.

Make sure the patient is admitted and not " under observation". Patients needs to be admitted and in the hospital for 3 midnights for Medicare to pay for rehab.

Yes

Is your loved one still in the hospital?

https://www.medicare.gov/coverage/is-your-test-item-or-service-covered.html