The newest map isn't orientated north, so the bottom is actually southwest... but the bottom
is the direction the enemy are coming from. Sorry about the confusion, but using a top to bottom shoreline made drawing it a lot easier than everything rotated 45 degrees.
Using this map below, which is properly oriented north, I've shown the enemy advance with a red arrow.
The ongoing gunfire with Monolith's "missing" squad is occurring somewhere on the extreme right hand side of the map, marked by the ???.
I've also given approximate locations of the 3 Mad Dogs and 3 Monolith squads.
Hope that helps clear things up.