Unsure about both the direct and reported speech in this particular case:

Question

Direct speech:

In 1917 she said: "The other half of the sum will be granted when he finishes (has finished) to instruct the three students he had committed (himself) to train."

Reported speech:

According to that 100 years old document the other half of the sum was to be granted (would be granted) when he had finished to instruct the three students he had committed (himself) to train.

What would be the right form for both cases?

I am not sure whether "himself" has to be added or not and also whether "when he had finished" can end in a future in the past like "would be granted" or "was to be granted". There are also other things like whether "finishes" and "has finished" can be both transformed in reported speech in "had finished" or "finishes" turns in "finished" and "has finished" in "had finished"?

Answer 1

You want to report:

According to that 100-year-old document the other half of the sum would be granted when he finished instructing the three students he had committed (himself) to train.

Notice: 100-year-old, not years old.

The past tense of will is would.

You backshift simple present finishes to finished. And in today's English we say finished instructing, not finished to instruct.

Alternatively, if you have has finished in direct speech, you backshift that to had finished.

The use of the reflexive himself is optional when to commit means to pledge or to promise.

Also, was to be granted is the backshift of is to be granted.