Did you try the emergency motor off :
Panic Buttons | 3DR Site Scan - Commercial Drone Platform
I assume all 4 props are reversed ? If not , it will flip.
When I do test , a tied down Solo, what I can tell is that the brain of the Solo will throttle hard to lift the Solo in vain, but I can turn it OFF using the controller.
In your case if the Solo get pushed down instead , maybe the barometer experience "vacuum" pressure and act different...maybe...and normal propeller motor shut down procedure wont work due to certain algorithm does not match.
However I always do tied down test and fly with MANUAL take off, are you on AUTO take off ?