"Academy Players must meet all attendance and participation requirements for training and games for their Academy team during the Academy Season. Failure to meet those requirements should result in removal from the Academy team" All players must provide a home address when they register and ussda does spot checks during the season for training and whatnot.
Uussda players are scouted or evaluated intensively during the season, showcases, & through the bi-yearly audits so I would imagine it would be difficult to "hide" out of area ringers, people would notice with all the connections nowadays, word would get around quickly I would think.