Reading what Sam wrote, the board didn't tell Yishan no. They just wanted him to add up the effects it would have. Which isn't just reasonable, it's a requirement if you're any kind of responsible corporate steward. You don't move on a whim, you have the pluses and minuses all figured out.

And no offense, but I find it hard to believe anyone other than Yishan and the board (and maybe some other investors) is privy to all the conversations they had.

It wouldn't be at all surprising if board members are 'nicer' to a ceo in front of employees than they are in private. It'd be kind of surprising if they weren't.