The 24-year-old left her family home in Grays, Essex, on July 4, and was last seen in this video walking along Derby Road, West Croydon, on July 7.
She has not been seen in the four weeks since. Police have arrested three men - aged 23, 27 and 32 - in Croydon earlier this week on suspicion of murder.
Her concerned mum Nicol released a statement, asking her daughter: “If you see this appeal please believe you are not in any trouble, we just want you to come back to us.”
The Met has now released images and CCTV footage of Owami on July 7, the last time she was seen.
Two photos show her in a shop in Croydon, wearing a white t-shirt, black jacket and black bottoms with sliders.
The video shows Owami walking along Derby Road, near West Croydon station, with a man wearing dark clothes.
As the pair cross the road, a white van pulls out from the parking space to drive off.
Police are urging anyone who saw Owami or has information to come forward, and in particular are hoping to speak to the driver of the white van.
Det Ch Insp Nigel Penney said: “We are working hard to find Owami but we really do need the public’s help.
“Owami is very vulnerable and the longer she is missing the more we worry that she has come to harm.
“As a result of extensive CCTV enquiries we have a clearer idea of Owami’s movements, but we still need the public to contact us and tell us what they know.
“We would obviously like to speak to the driver of the white van that passed Owami in Derby Road, but anyone with information should call.”
The Met has said this remains a missing person enquiry, however detectives from the Met’s Specialist Crime Command are now leading the investigation due to their “resources and expertise”.
A house in Derby Road - where Owami was seen walking on the CCTV - has remained cordoned off for several days, with tents outside and forensic units combing the house.
She told LondonWorld: “My heart was racing, I was so shocked.
“Police were chasing him to come out and then the police were there on the other side of the road wearing their body cameras.
“All the SWAT teams were at the house, from here, the garden, everywhere. They blocked all the windows.
“We know the girl came from West Croydon station to Derby Road and they’ve seen from the CCTV camera, she didn’t exit the road.
“They were searching upside down the whole house.
“They dismantled the mattress. They removed it now but they opened it in half and looked inside it.”
Tonight, August 3, exactly 28 days after she was last seen in West Croydon, officers will be speaking to the public and handing out appeal leaflets to try and find witnesses and gather more information.
Det Ch Insp Nigel Penney continued: “You can call and speak to officers, or if you prefer you can contact Crimestoppers who will never ask your name, trace your call or IP address.
“They are 100% anonymous and you can call them in complete confidence.
“Owami’s family are living through a nightmare and are desperate for news.
“I would ask anyone who thinks they can help to come forward - as the days pass the anxiety of Owami’s family will only get worse and your call could be the one they are praying for.”
Owami’s heartbroken mother issued a plea for her daughter to come home.
Mum Nicol said: “There are many friends and family who love and care for Owami and all of them want to see her safe return.
“Owami - if you see this appeal please believe you are not in any trouble, we just want you to come back to us.
“Please leave a message if you can to let us know you are okay, we are so very worried about you.
“This is such a terrible time for all those who love Owami and I am pleading for anyone who can help find her to contact police.
“Every day we hope to hear the news that Owami is coming back to us, your help might make it so.”
On Monday, 1 August two men, aged 27 and 23, were arrested in the Croydon area on suspicion of murder, and yesterday a 32-year-old man was arrested on suspicion of murder at an address in South Croydon.
They were taken to a south London police station where they all remain in custody.
Any witnesses or anyone with any information is asked to call police on 101 or contact via Twitter @MetCC. Please quote reference 22MIS025307.
To give information anonymously contact Crimestoppers on 0800 555 111 or online at crimestoppers-uk.org