The survivors regrouped, and hid themselves in the maze of blocked streets and burned out buildings that the downtown had become.
Here we see one of the surviving combat engineers using a flak robot to harass one of the walkers. He is assisted by what looks to be an airman armed with a PDW, possibly a gunship crew member.
While 57mm is unlikely to present much direct threat to the walker, it does prevent the advance of the associated powered infantry and give the main force a chance to withdraw south. Walkers that could be lured into the downtown blocks found many of their strengths nullified by the poor sightlines and hazards from ambushes and multilevel basements among the ruins.