Thank you! I couldn't figure out what I was doing wrong. I bricked 4 teensy 3.2 this way and only 1 of them came back when I bridged the cut with solder. On that one, the solder must have wicked down to layer 3. Time...
TL DR summary begins: Use (X axis, Y axis, mouse wheel) of one pointing device to control (horizontal scroll, vertical scroll, zoom), while other connected pointing devices function as normal, except their scroll wheel...