原本不过是个渺茫的希望，拖到天黑也未见得会更渺茫。

It is a forlorn hope at the best, and not much the forlorner for being delayed till dark.

你外公未见得肯答应，除非他弄清楚别的方面没有再开销他的地方。

Your grandfather isn't likely to consent to it unless he can make sure that he's not got any other drain on him.