[3] In 2019, he represented South Africa at the 2019 African Games held in Rabat, Morocco.

[5] Houlie achieved a 2022 World Aquatics Championships and 2022 Commonwealth Games qualifying time in the 50 metre breaststroke with a gold medal-winning time of 27.22 seconds at the 2022 South Africa National Swimming Championships.

[8][9] Day two of swimming at the 2022 Commonwealth Games, conducted in July and August in Birmingham, England, Houlie ranked twelfth in the preliminaries of the 100 metre breaststroke, qualifying for the semifinals with his time of 1:01.62.

[11] Two days later, he swam a time of 27.10 seconds in the preliminaries of the 50 metre breaststroke, tying Adam Peaty of England for overall first-rank and qualifying for the semifinals.

[16][17] At the 2022 U.S. Open Swimming Championships, held in Greensboro, United States, Houlie competed representing the University of Tennessee and helped win a silver medal in the 4×100 metre medley relay on day two, splitting a 50.96 for the freestyle leg of the relay to contribute to the final time of 3:43.44.