Squad C's approach goes well enough - the guards are cautious, alert, and look well-trained, but not unnecessarily hostile.
"I say, sirs," a man in some incredibly dapper salvaged-and-repaired pre-apocalypse clothing calls out from the wall. "I see your approach is not from the coast, but you are well-armed and move like disciplined soldiers - much better than the Raider rabble, to be sure. Come you to Invictus as friend or foe?"
"Friend," the Sergeant replies cautiously. The well-dressed man signals a gate guard, and a heavily fortified gate in the mighty walls sealing the city slides open.
"Enter, then. We can speak inside. It would not be gentlemanly to leave you outside in the sand, dirt, and danger if you have business here."
You can relay a suggested cover story to them by radio and order your Elites to do something, if you desire.
Squad D returns to The Shell without incident; while here, they will be healed for a small amount and restore some mana in the comfort of the Shell based on the number of days they stay. (Base of 2 HP and 2/3 of a Mana unit per day, with 3 days before the next week starts). If you garrison them and send out a different squad next week, they can heal while training (barring any unfortunate incidents, which will remove that particular day's rest/repair value). Also, at the end of the week you'll have another 10 Equipment to assign.
Finally, your food surplus is becoming narrow; immigrants aren't a fantastically common event, but a shortfall would be dangerous. You will officially get the Small Farm option (.3 Labor, 50 food) which costs .5 Labor to build and can later be upgraded to a Large Farm soon but basically you can make one whenever. I'd recommend doing it when you have enough spare Raw Materials that pulling the Salvagers off for that duty won't cause a stop in Equipment production efficiency and are concerned about another immigrant wave or a random crop shortfall event.