The app wouldn't accept a password, just a time and location to unlock. I'm not sure if that's better, but it technically sidesteps that issue.

I said plain text, not password. And it doesn't side-step anything because when you're in front of a judge and explain why you cannot provide plain text, they'll take your phone from you, get it to the location you tell them, and if none of that yields plain text, you go to jail. Two years, they give you for that.

Who has gotten two years for that and lost the appeals?

That only applies if there's a court order to reveal the data, not at random border checks.