Who decides where an immigrant comes from when most of them do not have any documentation such as a passport.
Anybody in that situation is immediately suspect IMO. They suddenly lose their papers on the last leg - how convenient.
"Where are your papers?"
"I lost them."
"OK, where are you from?"
"Bogoland."
"Fine, I have a ticket back to Bogoland, or you can have one for anywhere else who will take you. Your choice."
I have three members of my extended family working for the Home Office and the above conversation would have them in apoplexy, except one. He has to go out to try to apprehend wobbly asylum seekers by visiting dodgy businesses. He catches them then they get let off - so do the businesses.
The underlying problem has nothing to do with Hotel Rwanda. It is systemic failure.