After his brother lost the family fortune with rash investments, Gustave needed to earn a living. Rather than accept a position with the Belgian government to which he was opposed, he chose to travel to Egypt with the expectation of being appointed Attorney-General. However, before the appointment could be finalized, the Khedive died. Meanwhile, he became a member of the "high society" and proved, to the joy of his hosts, a gifted musician. During a lunch hosted by the British ambassador in December 1891, he met Prince Damrong of Siam, who had gone to Europe to search for a General Advisor for his half-brother King Chulalongkorn (Rama V). Following a hasty correspondence with Bangkok, the prince was able to offer Rolin-Jaequemyns an annual salary of £3000. Despite the opposition of his wife and his own poor health, he accepted. The Siam offer was his opportunity "to realize his dream to put into practice his principles of law and to ensure that respect for international law enabled a small, threatened country to resist the major powers."