150th NRL career match and scored a try in the 42–16 win at Robina Stadium. On 6 May 2017, Leilua played for Samoa in the test against England, starting at centre and scoring a try in the 30–10 loss at Campbelltown Stadium. On 7 June 2017, Leilua extended his contract with the Canberra club to the end of the 2020 season. Leilua finished the 2017 NRL season with him playing in 24 matches and scoring 10 tries for the Raiders. On 6 October 2017, Leilua was selected in the 24-man squad for Samoa in the 2017 Rugby League World Cup. Leilua played in all 4 matches, starting at centre in Samoa's disappointing campaign. At the end of the season, there was rumours that Leilua was set to be forced out of Canberra to join the Gold Coast Titans to ease their salary cap after a hot-and-cold mixed form year. 2018 After playing in the World Cup, Leilua along with Samoan representative team-mates Josh Papalii and Junior Paulo were confronted by coach Ricky Stuart after they arrived at pre-season training overweight, the trio were forced to join the dreaded "Fat Club", doing extra cardio training sessions to get back into a respectable weight. On 23 June 2018, Leilua played for Samoa in the Polynesian Cup against Tonga, playing at centre in the 38–22 win at Campbelltown Stadium. In round 17 against the Canterbury-Bankstown Bulldogs, Leilua scored the winning try with a minute to go after the Raiders scored 3 tries in 6 minutes to fulltime from a 28–14 deficit at Canterbury's spiritual home ground of Belmore Oval. After scoring the try, Leilua taunted Bulldogs defenders, brothers Josh and Brett Morris in which Leilua was criticised by coach Ricky Stuart and Parramatta Eels legend Peter Sterling, Sterling commenting, but it was the post-try spray he gave the Morris brothers that raised Sterling's hackles the most. "This is Josh and Brett Morris, who have done everything in the game and achieved a whole lot more than BJ looks like he will," "You don't disrespect those kinds of players in those situations where you've been poor yourself up until that moment." On 26 September 2018, Leilua was a shock winner of the Centre of the Year award after beaten clear favourite, the Sydney Roosters boom youngster Latrell Mitchell. Leilua finished his rocks and diamonds 2018 NRL season with him playing in all of Canberra's