Just Another 3 Way Wiring Question

I’m in the middle of switching my light switches to Homeseer z-wave dimmers and companion switches. My first 3 way looked and acted as expected (line in one box, load out of the other, 3-wire travelling between). I have also seen the line and load in one box with just the 3-wire going to the second box. I’ve capped the black traveler at both ends and everything works fine.

My last 3 way has thrown me for a loop. The line box has the 2-wire coming from the breaker and a 3-wire travelling to the second box, but there is no 2-wire to head to and from the light fixture. I’d expect it to be in the second box, but that box only has the 3-wire.

I can setup the primary switch without the companion by using the black wire in the traverse as the load and then connecting the load and neutral in the second box to complete the circuit. I can also add the companion switch in by using the red wire and a pigtail from the neutral in the second box. The primary switch works fine, but the companion switch will only turn on and get brighter. The companion switch will not turn the light off or dim. The primary will.

My best guess is that the light is actually connected to the load or neutral between the two boxes which is why the switch works fine if I complete the circuit in the second box. Any thoughts on how to complete the project?

Thanks for the help.