Rico used the force of the previous attack from Dror to run further away.
Most of the buildings in the city were constructed with special material that could withstand heavy explosions, especially those places where warriors visited and there was a chance for a fight to occur.
Of Course this could never obstruct someone in the true warrior realm, but they would still have to use their warrior essence to break through the walls.
Even with all this, the stability of the whole building was reducing at a continuous rate with the true warriors fighting, even the outside barrier was starting to feel the pressure.
But both the teams were holding back their power in the fight due to their own reasons.
The rebels didn't want to alert the city enforcers and Madam J didn't want to destroy her headquarters when she could just create enough commotion to attract the enforcers without destroying the entire building.