I'm not currently facing any problems, I think, but the reason for that may be some of your concern.
I last used Wwise about two years ago. I'd tell what version I had then, but I already uninstalled it... Anyway, I just upgraded 2019.1.7, and have Unity 2019.2.16f1. I created a blank new project and tried to integrate Wwise into it from the Wwise launcher.
Hitting the Integrate button in the Unity project list gave me the usual screen, with the Integrate button grayed out and un-clickable at the bottom. I went through a while of futile internet searches and repeated attempts which were greeted with the button remeining unusable. Then one time, I scrolled down in time to see the button temporarily colored. After a second, it grayed out.
In my frustration, I reopened this menu, scrolled down real fast, and successfully hit the button before it grayed out.
It appears that I have a Wwise project fully functionally integrated into my Unity project at the moment. All seems well.
But I don't know why the button was inactive in the first place, and I probably wasn't supposed to do what I did to work around it.