Could you give a little more context? With just what you've written, I'd say that the phrase "as just as fair" is something you found in literature. 'Just' is giving a person what is due to him; 'Fair' is giving equally to two or more individuals. "As just as fair," then is saying that the action was equally just and fair.

Yes, they are.

The first one is correct, but the second doesn't make sense in English.

'Leave' is time off from work, and is usually used when longer periods of time are taken off, such as when a baby is born or a family medical issue comes up. That time could be paid or unpaid. It is not, however, generally used when referring to vacation time. If you took a long weekend off, whether paid or unpaid, it would not be considered 'leave'.

Here Father = Dad, so it's not a priest, but simply the proper name for the author's father.

That's an awkward use of the phrase, but "waiting is over" means that whatever you were waiting for (maybe for the app to load?) has been completed. Since the activity has been completed, your time for waiting is over.

You could say: To make him stay, the manager assured him of a raise. That is to say that the manager assured him that he would get a raise. You would not say that the manager assured him a raise. (The word 'of' is essential there). It would be better, more common, to say that the manager promised him a raise. You also would not say that the manager 'ensured' him a raise. You could say that the manager ensured that he would get a raise, but that means something other than what the sentence is giving. To say this would mean that the manager did something to guarantee the raise.

In this context "to break out" means that the sores appeared on the skin, typically many of them, all over the body, and rather quickly. You'll see this phrase used similarly in "I broke out in hives" or "I broke out in a rash" or "My face broke out (with pimples)."