There's a difference between spending a week's work experience on a base and the Engineering Undergradute Placement Scheme offered by the RAF.
I spent a week on the GEF at Leeming a while back which was sorted out directly with the station, irrespective of my ATC involvement.
The Gap Year idea is totally separate, a friend of mine on my UAS recently returned from a year at Waddington where he was part of a team of undergrads who were all in the same position. He held the rank of APO and was paid a salary as befits that.
He returned to the UAS and his last year of university this year, and when he graduates he'll be on the next IOT.
Apparently it's not been that successful though and may be stopped.