Once you give him the items the achievement will pop.
Once you have completed that quest you will return to the overseer interviewing 3 possible subjects for her plan, the first 2 wont help but the 3rd one will become her subject and at the point the overseer asks you to suit him up and will tell you to collect the pit boy and the suit to give to him. which you will get by following the DLC's quest line. For this achievement you need to give a suit and pit boy to a settler at vault 88 you won't be able to do this until you have completed the the quest explore the vault.
