Are you installing this on a live site that I can access? Or is it a local site?
If it’s something I can login into, then I can go ahead and see what’s going on. All I would need is a temporary login.
Is the Genesis Framework (Parent Theme) already installed? That would need to be installed before you install and activate Oasis.
I’d also check to make sure you have the latest version of WordPress updated.
I’ve never ran into this issue before, but I’m sure I can figure out what’s going on.