ESA for Polish person coming from Canada

I have a client who has bowel cancer and is looking to see if he can claim ESA.

He is Polish, 29 years old and lives with his mum and sisters. He spent 6 years in Canada and was diagnosed with cancer, in Canada, in April 2014. His family then all came to Scotland to live.
Mum works part time and gets CHB and TC for his sisters. Dad also came over but does not live with them and he is working. Client has never worked in this country. Will he be entitled to IR ESA?