Welcome to the Wyze User Community Forum @jbdbmcbride!
Yep. You are on the right track.
The room sensors do not have any integration into rules or routines for triggers or actions. The only thing they can do based on motion sensing is to include themselves or exclude themselves from the averaging feature that adjusts the measured temp to the average temp in the house.
Alexa doesn’t have any control over the Thermostat state either. So, to tie the systems together you will have to be creative with a Wyze plug (or several). I do this with Alexa voice control. See my post link below. Alexa can talk to the Ring Motion Sensor and the Wyze Plug. the Wyze Plug can talk to the Thermostat.
Alexa Routine uses the Ring Motion Sensor in the room as a trigger, actions a Wyze Plug to turn on (for x min). A Wyze Rule uses the Wyze Plug on as a trigger and actions the thermostat to change state.
Here is how I did it with Voice Commands. Using the Ring Motion Sensors is an easy substitution.