One of the (many) problems with this case has been that the early reporting was not consistently accurate, and by the time the MSM picked up the story there were inaccuracies that had already spread like chinese whispers. So, for example, it was said that her family were from Essex but that she'd gone missing after leaving home in Croydon; and then later it was confirmed that she'd last been seen leaving the family home in Essex where she lived with her mother and brothers. Also, it was widely published to start with that she'd last been seen on Monday 4 July but not reported missing until a week later on 11 July, whereas the Essex Police investigation reference number makes it clear she was actually reported missing on Wednesday 6 July, which has since been confirmed by family.
I'm saying all of this because the (otherwise reputable) source I'm about to quote is dated 4 August and is quite vague in how it words what it says, so imo it should now be treated with a certain amount of caution. However, what it says, supposedly quoting her mother, is:
“She said she was going to the gym, so I went to do the school run for her youngest brother while Owami took a shower. Within 20 minutes I was back.
“Later when I became concerned, I used the Find My iPhone app which is something I do with all of them. I was curious where she was and she wasn’t at the gym.
“I’ve never known her to know anyone in Croydon. She’s an Essex girl. She likes hanging out in Romford. She doesn’t have many friends, just one best friend.
Tell me where my daughter is, pleads mother of missing Owami Davies
As I say, it's vague. I assumed when I read it (because of the combination of school run and shower) that this all took place in the morning, but I've since read that Owami left home around 4pm, so perhaps it referred to the afternoon school run.
Similarly, it strongly implies that Owami's mother discovered in fairly early course that she (or at least her phone) were in Croydon - but it doesn't actually say that. And if it was evident on Monday 4 July that Owami was in Croydon, it begs the question of why the missing investigation was only handed to the Met on 16 July (again, based on the investigation reference number, which changed to a Met one that day). It's sad to think that if Croydon Police had been alerted to look out for her immediately, the encounter in Clarendon Road might have been handled differently. There may be all sorts of reasons for that, to do with how long it took Owami's mum to report her missing, how the police handle these sorts of enquiries, or all sorts of other details that haven't been reported (e.g. where else her phone showed up or how quickly it went offline, or whether her bank cards had been used and what for, etc, etc).
Afaik, nothing has been said about any contact after that first day, and nothing reliable has been said about potential reasons for her going missing. There's been no talk of an argument or of ongoing problems with family, relationships, studies, money or mental health. Her departure seems to be a complete mystery, likewise the vulnerable state the images of her in Croydon show, and while some social media has seemed to imply that she may have "gotten herself into trouble", nothing of that sort has been confirmed by the police, the media or her family.
It is, as you say, all very strange. It reminds me very much of Richard Okorogheye's disappearance. We can only hope it doesn't end the same way.
JMO