Immediately after arriving at Aldershot Town on 13 February 2017, Oyeleke was loaned to Isthmian League Premier Division club Canvey Island for one month to gain match fitness. He scored one goal during his six appearances and suffered a hamstring injury during the final match of his loan. On 1 June 2018, Oyeleke returned to the EFL by signing a one-year contract with League Two club Port Vale. After recovering from an injury picked up in pre-season, he started the 2018–19 season in a central midfield partnership with Luke Joyce. On 15 September, he scored his first goal for the "Valiants" in a 2–0 victory over Northampton Town at Vale Park, which was later selected as the League Two goal of the weekend; in addition to this he was also named on the EFL team of the week. However he picked up a hamstring injury at the start of the following month and was ruled out of action for a few weeks. A calf injury in April saw him sidelined for the rest of the 2018–19 season, leaving manager John Askey to comment that "I think all season Manny has struggled to get right. Going into pre-season he was injured and then he had to start playing to get his fitness. That has affected him this season... but we all know that Manny will be missed because he had shown his ability. He has looked a good player." He signed a new two-year deal in June 2019. He picked up a hamstring injury two games into the 2019–20 season and was initially ruled out of action for four weeks, though his recovery was slow and he was sent to St George's Park National Football Centre after five weeks in order to better aid his recovery. He made his first start in seven weeks on 28 September, however lasted just ten minutes before making a grade three tear in his hamstring and facing another extended lay off. He underwent surgery on his hamstring in October and returned to fitness in February. He made made only three starts before the season was ended early due to the COVID-19 pandemic in England. Able to play as a central midfielder or at right back, Oyeleke has described himself as "quite dynamic, strong, good on the ball and a team player". Aldershot Town director Tommy Anderson stated that Oyeleke is "a very solid box-to-box midfielder... very good at protecting the defence but also very good at going forward as well" and "a very good ball player, he is someone who looks to dictate play, he loves to control the midfield.