Ollubi transferred to Harding University in Searcy, Arkansas, in 2019, but only spent one year there as he decided to leave when they discontinued his economics major.[2] In his one season with the football team, he appeared in 12 games, recording 23 tackles, 5.5 sacks and a fumble recovery.[3] In 2020, Olubi joined San Diego State University, having been given a chance as a walk-on after convincing the team through a coach who knew one of their coaches.[2]
Olubi saw limited playing time in his first season with the football team, a Division I FBS program.[3] In seven games as a backup, he recorded 15 tackles, five of which were solo.[3] His highlight of the season came against Hawaii, where he recorded a 71-yard interception return touchdown.[1][4] Prior to the 2021 season, it was announced that he had been put on scholarship.[2] He was also voted team captain by teammates for the season.[2] Olubi appeared in 14 games in 2021, seven of which he started, recording 53 total tackles, two sacks and two forced fumbles.[3] He was among the 88 nominees for the Burlsworth Trophy, given to the best player who started his college career as a walk-on, but ultimately did not win it.[5]
On September 1, 2022, Olubi was signed to the practice squad of the Indianapolis Colts.[9] He was elevated to the active roster for their Week 16 game against the Los Angeles Chargers,[10] and made his debut in the loss, appearing on nine special teams snaps.[11] He appeared in one further game in 2022 and posted a single tackle.[11] Olubi signed a reserve/future contract on January 9, 2023.[12] He made the team's final roster in 2023.[13]
On January 8, 2024, Olubi signed a one-year contract extension with the Colts.[14]
