Police will meet Saudi Arabia's Al Ain in their final match.
Police lead the standings with nine points.
Police will play hosts Kuwait in their next match.
The Gulf championship is scheduled to start on Tuesday and will conclude on February 10.
Al Rayyan did not face opposition in the first two sets in their 67-minute match. But in the beginning of the third one, they trailed 6-8. But midway, they managed to catch up with Al Khor and forged 21-19 ahead.
Al Hilal, Al Ain, Dar Kulaib, Al Seib, and hosts Kuwait are the other teams in the championship.
The draw was held under the supervision of Hussein Imam Ali, the QVA Technical Director.
Though the result took Al Khor’s points tally to 12, their position remained unchanged in the table.
The victory was fourth for Al Ahli in 11 matches and it also ended a 10-match winning streak for 25-time champions Al Arabi.
The 29-27, 25-21, 25-21 victory was an eighth one in 10 matches and enabled Police to take the second spot with 23 points behind leaders and unbeaten Al Arabi.
Camilo Soto-coached Qatar lost narrowly to South Korea in their final pool match.
The second straight victory all but ensures Qatar’s berth in the semifinals.
Camilo Soto-coached Qatar will take on Australia in their next match on Wednesday.
The winner of the eight-team tournament will book their berth at Tokyo Olympics.
Al Arabi lead the standings with 25 points while Police are second on 20.