Not true both of you.
I have been in this industry for twenty years and the number of "students" who attempt to get into this country for reasons other than their stated aim is enormous.
British universities are full of ghost people.
They get in and then simply evaporate - some of my "students" have done just this.
I have been involved with the Special Branch on several occasions.
He has a visa problem - thankfully after the eleventh of September 2001 we are all cautious.