Simple reason why Cobel and Mark/Devon weren't shown speaking

The discourse about this blows my mind. They literally explained that Cobel isn't giving away anything earlier, why would that change? You think they added that detail for no reason? I keep seeing comments like "there's no way they didn't grill her for all those hours they were standing there", yeah well, what can they do if she doesn't answer? People lack basis comprehension and yet are so quick to label things bad writing.