Extending contracts for players with no work permit

My Brazilian coach came up with a 17-year old whom he highly recommends. Scouted the player with a couple of other scouts who had a higher JPP rating and they all say that he will become a "leading star for most premier division side". However since he will not be gaining a work permit, they recommend me to send him to my Belgian feeder club. My question is..since i think i can give him just a three year contract and he will not be joining my club until he turns 18..can i extend his contract even if he does not gain a work permit (which is highly possible since he would have spent just two years there before his contract runs out)