The 19-year old centre-back is one of the rising stars of South African football and is on the verge of signing a two-year deal with the Whitecaps following a successful trial last year.
"Ethen is the consummate professional - since the age of 17 he's had some of the top SA clubs trying to turn his head with the offer of contracts, but Ethen knew he still needed time to develop his game if he were to make it overseas," said ASD director Mike Steptoe.
"To his credit, he has been remarkably patient in his pursuit of a professional contract, which isn't always easy when teammates are moving on. His family have been incredibly supportive too, his father Victor in particular, and we are all thrilled that Ethen's hard graft has finally resulted in a contract.
"Ethen trialled with the Whitecaps late last year. They have a great set up and we are confident Ethen will continue to develop under Head Coach Martin Rennie's care and guidance."