In 2015 he was part of the Fiji national under-23 football team that managed to win the 2015 Pacific Games. Koroi played in all six games, including the final against Vanuatu that Fiji managed to win after a penalty shootout. In the preparation for the 2016 Summer Olympics Koroi was part of the side that did a tour in Spain and Brasil, however he was not part of the final squad for the Summer Olympics. This was because Fiji chose to pick the experience national team goalkeeper Simione Tamanisau. Frankly, after this tournament he became the first team goalkeeper for Suva.