We don’t know that the previous student called Mo Farah was the real Mo Farah.
For all we know there could have been loads of them up and down the country all being trafficked on the same documents.
Also - surely the foster mother must know more than she’s saying because the supposed trafficker was her brothers wife. And She knew the life he was leading yet let it to go on till SS turned up on her doorstep with him when she lied and said yes he’s my nephew. Couldn’t she have said then what the reality was.
Then there’s the part where the random lady turned up in the restaurant with the tape from his mum. People must have known where he was.
I can recall my husband and his friends getting cassette tapes from their families when they were studying in the UK. It was really upsetting seeing what it meant to them and it’s the cassette tape Sir Mo got that got me in the chest.