Brian,
In your "regular DAQ" that you posted, I can see that you've combined two examples together, one for synching up the clocks, and one for synching up the start triggers. The way you have done this seems to be correct, except for one small thing.
If you dig a little deeper into the example on synching up the start trigger, you'll see that you have to tell the Trigger Config VI that you want to turn the trigger ON; therefore, when you call this VI and wire the RTSI1 for the trigger line, there's also an input to the Trigger Config VI called "Mode"--you must wire an "on" to this. (Do this for both slave boards.)
Try that first.
Mark