 Pari gbolohun ti o tẹle: Ni Oṣu Kẹta ọdun 2015, a darukọ Viljoen ni ẹgbẹ ikẹkọ ti o gbooro ti South Africa labẹ 20 gẹgẹbi apakan ti igbaradi wọn fun 2015 World Rugby Under 20 Championship. Ko ṣe afihan ninu ere ọrẹ kan lodi si Varsity Cup Dream Team tabi irin-ajo ere meji wọn ti Argentina, ṣugbọn o wa ninu ẹgbẹ ikẹhin fun : 2015 World Rugby Under 20 Championship. Àwọn ojúewé wọnyí jápọ mọ 