here you go
first you have your team go east along the map edge, and then move toward the side of the main building, the side with the truck, get to the roof, then down to 2nd floor
now the commander is inside the west room of 2nd floor, either have someone sneak in and break the alarm, or rush in and kill him before he use the alarm
as for deathclaws.. since all the weapons suck at this stage, I suggest you get a few people line up horizontally and burst AK-47 at the deathclaws (lining up is to avoid hurting your own team mates), an adult deathclaw have around 250 hp, shotgun works nice too if they're close enough, but don't depend on it
If you're playing on Hard or Psycho difficulty, god help you, because my 3 man team bursting for 3 whole round at point blank range can not kill a baby deathclaw.. it was severerly wounded when it killed me (that was hard difficulty)