Maybe something like this would work if I plug it in in the attic and run the wire down with the existing thermostat wires?
Your 2nd picture shows the 24v transformer, trace the wire from R terminal back to the transformer. The other wire on the transformer will be the C wire, trace that wire out to see where it connects. Worse case you can cut that C wire, strip it back a bit and use a wire nut to connect it back together with the C wire adapter. If you go this route, make sure you turn off breaker just to be safe.
Is there another screw terminal right here?
Is that blue wire available at your thermostat?
If so, connect the blue wire to this terminal and to your C terminal on the wyze.
Your thermostat wiring needs to be re-sleeved or insulated with electrical tape, the insulation is pretty compromised.
Excellent!
