Earlier quoted context omitted.
What do colleagues have to do with anything? The better question is in what ways do you trust, and not trust, the company you work for? And the answer to that can be very complicated, and depend on the company a great deal. It also depends on who might buy the company in the future, and they might not be trustworthy at all.
The scenario is someone in a work environment, lying and defrauding in signed documents. Where does the workplace dishonesty start and end? Does the person think that their colleagues have the same rules, or different rules? How does that affect their work environment? (Incidentally, I'm sick of HN downvoting legitimate comments.)
Nobody is entirely honest to everyone about everything in their workplace. You really think everyone is actually sick on every single sick day, or that every single doctor's appointment on their calendar is a real doctor's appointment? People never make excuses to their manager that are lies? Managers never lie to their employees about a justification or a deadline or a promise or a policy?
Workplace dishonesty is everywhere. Because workplaces are made of human beings. It's just something you learn to manage in a realistic way. People are mostly honest, but they're never entirely honest.