I’m sorry to hear that your brother is suffering for the last 2 months.
Stomach ache that is persisting needs to be further evaluated. Also, no clear result on endoscopy doesn’t mean that there is no other problem.
I suggest you meet an abdominal surgeon as per your convenience. I could see your brother physically, if possible, at one of my clinics.
Next Steps
Pls meet me at one of my clinics, or have a tele consultation with me, so that we can further evaluate and plan for your brothers treatment.