I feel similar to the two people you're describing. I'll give you an example of what they may be thinking.
I am a native-born American, raised in America; but I was slowly conditioned, over years, to a partially Japanese mindset. Then I moved to Japan for a little bit, worked a contract, and moved back. At this point, both cultures have really impacted my mindset.
The job I have now is the first where we have standard, daily standups among engineering teams, and as a software engineer, I have to attend these. Well, it's been months now, and I still have similar trouble with them.
One thing I would definitely try is:
- Develop a friendly rapport with each of these two engineers, if you haven't already.
- Use that rapport to talk to each of them one-on-one, outside of standup, very regularly.
- Keep both in the standup meeting, and let everything continue normally.
A Perspective Probably Similar to Theirs
In my mostly Western, but now partly Japanese mind, the idea of a standup where everybody "collaborates", "openly discusses issues", etc. may just be incompatible with certain parts of the world. This doesn't exclude all of Asia, as for example, many Indians seem very comfortable in this setting. Some countries though, such as Japan, can be quite reserved and regimented, to the point that a standup is probably fairly antithetical to the business world norm.
The thing to remember is that, when you're sharing information openly, every single person you share it to can potentially use it against you. Yes, I completely understand the Silicon Valley mindset about the positives here. Yes, I realize many companies have used it to their advantage. But people are people, and they are not perfect. And any person in the (potentially virtual) room during a standup has the potential to use your information against you or against someone else.
I don't care how strong a given team is; no one is perfect. And if information does not look perfect on the surface, any flaw can potentially cause problems. Even if it is not misused, at least not intentionally, it can still be misinterpreted, lead to a loss of face, or anything else. This is simply a grim reality of this world.
Now, that said, some cultures, such as the Japanese culture, take this into consideration and are far more prone to exercising caution in everything they outwardly reveal. In fact, this is one thing that divides Japan from some other Asian cultures. Some individual people will be more cautious, other individuals less cautious. But culturally speaking, the typical dial is certainly turned up.
And...They're right. I mean, how many times have you had other people turn things against you, develop worsening attitudes toward you, and so on? How many toxic bosses have you had to work for? If no bosses, then how many toxic coworkers? Neighbors? Family members? And even among your closest friends and family, have any of them ever let you down?
The thing is though, your points are merited as well. In fact, neither approach is a silver bullet to success in this world, and both are valid strategies. Each approach comes with pros and cons. But take it from me: Once the other perspective is engrained into you, it is very difficult to leave it completely behind. Turn the dial down on it? Yes. Remove it altogether? Not likely.
The Reports You're Getting
As for the potential misreporting of things: Without me seeing it myself, it's possible they're just using words like "great", "fine", "good", and "okay". These are subjective words with subjective meanings. That means that, depending on the situation, there can be a lot of leeway in using these words while still being perfectly honest. Because, again, such phrases are subjective.
Similar things can happen with estimations. If they think something's going to be a day late, and you ask them about it, they may then tell you it's estimated to be on time. And in this case, they may just be thinking in the back of their minds, Well, maybe I'm just not working long/hard enough. Maybe I'm just not trying hard enough. ...If I just pull it together, then yes, I really can get this submitted on time. And if such an effort fails in the end, well, they were only really giving you an estimate.
In either case, without me seeing it personally, they may very well have not been attempting to mislead you or be dishonest.
Reiteration of the Recommended Solution
So how can you "fix" this? How can you convince the two individuals to be more open and have more trust that there aren't going to be negative consequences? ...There's probably not a good, general-purpose solution that doesn't take a lot more time than you have available.
How then do you deal with this otherwise? By keeping everything going just as it is now, except that you also build a rapport with each of the two engineers, and you use that rapport to communicate with each one individually. Rather than working against the grain, your best bet is to go in the same direction as the grain, so that you can truly build a bridge.
Don't pull them out of standup or do anything else like that. That will almost certainly make the two engineers feel horrible and will probably burn every bridge for quite some time, if not for good. Keep them in standup and act, even towards them, like everything's perfectly normal and fine.
However, do not keep pushing them to build a bridge to you; instead, build a bridge with them. Understand that they likely feel the need to protect themselves within a group, no matter what you say. So to get candid responses from them, provide the setting through a rapport and through casual, continual, but completely off-to-the-side communication.
And by building this bridge with them, you will ideally maintain a team with a more diverse perspective, whose horizons will include more than just the Western mindset. And having a mixture of both Eastern and Western perspectives, this team will ultimately be stronger for it and able to tackle a larger set of issues in the end.