I think you mean Steve Reich
It was Reich who used two very-slightly-out-of-sync tape loops in his 1965 piece "It's Gonna Rain".
Eno claims to have been involved with the Scratch Orchestra (I don't ever remember him performing, but it was over 40 year ago) in which case he would *definitely* haveknow about Riley, Reich and, with a bit of work back then, Glass.
I am unaware of any Cage work using tape loops.