Please disregard. The installation scripts were deactivating an existing kernel extension before activating, hence the extra prompt.

Some corrections (that I unfortunately cannot edit into my original post!) NSRunningApplication.activateWithOptions isn't deprecated, but the option NSApplicationActivateIgnoringOtherApps is. Instead of NSRunningApplication.yieldActivationToApplication I meant NSApplication.yieldActivationToApplication. Instead of NSRunningApplication.activate I meant NSRunningApplication.activateFromApplication. These corrections aside, I'm still looking for an answer to my original main question.