Yea, the chances of something going sideways is too great for it to be staged. Heck, even if the shooter wasn't just trying to play out an epic 'suicide by cop' scenario, you have to remember the Republican base itself is split on Trump, despite appearances. I'm sure some within it with a more libertarian bent aren't too happy with the fascist-like talking points coming from the Trump camp and I wouldn't be surprised if one or two of those think taking out Trump would be the best way to reclaim their party.