UPDATE - Just for the heck of it I put a 150nF capacitor across the switch (input pin to ground), and the homing operation of the z-axis completely changed. The direction changed and it found the limit switch. Must have been picking up stepper noise. I hope this was really the fix.

I have 60mm set for the max Z travel, which is the mechanical limit. I have tried going larger, but nothing changed. I am using an arduino UNO for my controller. As I mentioned, the X & Y portion of homing works fine, and the switched themselves are functioning as they should. The switches are all mechanical. In this case the switch doesn't seem to be the issue because the axis never travels up to the switch unless it is close when homing is called. Below is the alarm. The thing is, it never stops when it hits the switch, and never pulls away.