Terminal ileum ulcer = Crohn's?

Hello Doctors, My dad had episodes of black stools, abdomen pain, loss of appetite, lost around 15 pounds weight in 3 months. Got hospitalized twice, had endoscopy, colonoscopy, ct scans 2 times for now. Gastro. also took sample for biopsy to test for tuberculosis which came negative. They were suspecing either tuberculosis or Crohn's going by symptoms. Also they seen small ulcer on terminal ileum. Thats all I could understand so far as I was quite new with all this. My father is fine now since he started ayurvedic treatment. He got 80% relief from abdomen pain, no black stools episodes now, weight is stable, can eat everything. Remaining thing is mild abdomen pain and pain in left rib cage upper side, specially when he sleeps. So I have 2 questions- 1)Having ulcer in terminal ileum alwz means Crohn's ( or any IBD) ? What if it gets healed naturally. 2) what tests needed to diagnose Crohn's ( other than ct scan), a seprate biopsy would required ? Please guide, thanks.