In his response to the question, the eminent Muslim scholar and renowned Da`iyah, Sheikh `Abdel Khaliq Hasan Ash-Shareef, states:
So far a Muslim intended to stay this period which is 15 days then he has to observe complete Prayers during the stay. He is not allowed to shorten Prayers if his intention to stay for a period longer than four days. So, he has to perform complete Prayers during the stay.