She's not the only one who promised to stay alive, and not take any unnecssary risks. Sam can tell she's hesitant, and he doesn't blame her, even if he doesn't completely know the reasons why. It doesn't occur to him that she's thinking of the time he went to Steve and Bucky to try to do something stupid.

"To someone looking for you." He's not willing to say Albert's name, or even give a location - if there's anyone watching them or listening in, they're gonna find out anyway when he takes Terezi there, but at least then Albert will hopefully have enough time to do whatever he needs to. There's no need to give them a head's up.

"Will you trust me?"