A problem is that you can find them long before being given the quest by Jake and being Super Mutants you shoot first, you don't try and talk to a Super Mutant, it is just not the way of the wasteland normally. As I didn't start my SS2 quest line until after I had been questing for awhile, in a previous game run through I messed up several of these quests finding them before I was supposed to. Not sure if it is feasible, could it be similar to Kellogg's home in DC, could there be a way some of these doors/quests be locked/inaccessible until you get the quest given to you.
In order to find the button under the desk in Kellogg's home, you have to be on the quest with Nick. If you get in Kellogg's home before starting the quest the button is not there to open the secret room. After killing them all (the Super Mutants) several times, thanks to this post I decided to talk to them and now have my chalk for ASAM vendor unlocked. Side note, in a previous game, I had acquired over 100 ASAMs from various vendors without even starting the SS2 quest line from the Stranger/Jake.