Vihiga beat Nairobi City Stars 2-0 at Mumias Sports Complex to move within a point off leaders, Ushuru on 41 points.
Ochieng shot Vihiga to the lead in the 19th min before Okullo doubled the victors’ advantage 10 minutes to the final whistle.
Okullo’s celebration was, however, cut short by a booking after he was shown a yellow card for unsporting behavior.
City Stars’ Ezekiel Omula was the first to go to the referee's book in the 73rd minute.
Vihiga dislodged Wazito on second place thanks to their superior goal difference while KCB completes the top four.
The first four positions are only separated by two points with Ushuru taking charge of the wheel with 72 points.
Vihiga United will square it out with Ushuru in one of teh two games left to the end of the season.