It's more likely than not that they have enough evidence to win a conviction at trial. The DA's office does not want to lose high profile cases, they would be prepared for trial, and worked through all the flaws in their case, well before this month.
Now, there's always the possibility they lose. The Weinstein case may be headed for a hung jury, or a split verdict. And I am sure that case was very well prepped. I don't even listen to Lanez since 2016 or so, and I hear Meg only at a womans house or Lyft, or whatever. I'm more interested in the legal process than any sort of bias towards either party involved.