Here's my thoughts....
The temp will go up until so something melts!!!
Should the Auber fail, you will ruin your SI in my opinion...Here's my rationale ...
If it's stuck on, it keeps producing power in terms of Watts.
The thermal loss occurs in units of Watts through the walls, top, stack, bottom, etc.
Watts-In less Watts-Out determines the temperature rise the inside of your smoker experiences.
Now consider the insulation is very good, where it has a double walled container and high temperature fiberglass. Notice your unit is cold to the touch in most places? That's better than your household oven by far. Except at the very bottom or at point of heater element attachment... Those areas are a little warm but not scolding.
Let's just assume watts-out is negligible or zero for the simple calculation.
So if watts-in remains at 700 Watts and watts-out is zero.... The net add is always 700W ... Integrated over time is energy in terms of watt-seconds ... And alas the temperature will go up to infinity ( or in reality something fails first like wiring melts, heater element fractures from its own heat and opens up electrically....).
Steve