You could try using Teamviewer, though you probably won't get the full framerate you're wanting (another lesser known thing is this program does work on a LAN connection too, you just type the IP of the machine also with Teamviewer that you wish to connect to), so the KVM switch is probably the only real way, though you'll need to find one that's better than VGA, preferably HDMI or Displayport would be the better option.