As much as he has his own suspicions about his teammates (some more so than others), he doesn't express them out loud. He has his ways of dealing with trouble when it comes down to it, which seems almost contrary to his obsession with sticking to well laid out plans, but if you really think about it? He's a big picture kind of guy. Stick to the mission, follow through with the objective, whatever it is...they're all end goals rather than step-by-step checkpoints.

If Sombra is going to screw them over in the end, well, he'll deal with it when it happens. It's not so much that he likes to give their most brilliant informant and hacker that could easily turn on them at the drop of a hat all this leeway with how she conducts her business, but he just isn't a micro manager. It's not his style. Anyone who works with him knows what they'll be getting into. They just gotta be smart about how to escape him should they cross him, and well, Sombra is excellent at that. Even he isn't so sure he'd be able to hunt her down.

"Drop it," he says to Widowmaker, then turning to Sombra. "You know what you're getting yourself into?"