You are correct re. Daniel 9 written in Hebrew. My oversight.
Strong's Interlinear translates directly from Hebrew, Aramaic, and Greek.
It includes "he" in Daniel 9:27 because a covenant is between persons.
Because "he" was and is Messiah the Prince.
Who announced His New Covenant in Matthew 26:28.
And fulfilled it at Calvary.
When you read a Hebrew text, you understand the full meaning of what is written. If there is ambiguity, you understand both meanings. When a translator translates into your language, he cannot translate both meanings at once, he has to choose. The translator chooses according to his religious beliefs, and he chooses the option that seems more appropriate to him, and he can make a mistake.
There are other places in Scripture where translators in most translations have chosen the wrong meaning. For example:
That seeing they may see, and not perceive; and hearing they may hear, and not understand; lest at any time they should be converted, and their sins should be forgiven them. (Mark 4:12)
In the original Greek, this verse deviates from the norms of the ancient Greek language. The negation "not" applies only to homogeneous members of the sentence, which have the same form. Here, the last word has a different form, so "not" does not apply to the last word. The entire sentence should read as,
so that they see with their eyes, but do not perceive; they hear with their ears, but do not understand, lest they turn, and their sins will be forgiven
and their sins will be forgiven - The sins of the Jews will be forgiven without their repentance.
A professor who taught ancient Greek at universities explained this to me at great length.
Another teacher, who taught Hebrew at the university, explained to us that the prophet Isaiah's prophecy is written exactly the same way, the last two verbs have a different form, and therefore do not have the signs of negation, like the previous members of the sentence:
Make the heart of this people fat, and make their ears heavy, and shut their eyes; lest they see with their eyes, and hear with their ears, and understand with their heart, and convert, and be healed. (Isaiah 6:10)
and convert, and be healed - here there is a sense of the assertion that in spite of the previous members of the sentence, which speak of the coarseness of the heart, the deafness and blindness of the Jewish people, this people will be converted and will be healed.
When you read it in the English translation, and when I read it in the Russian translation, the meaning is lost, it seems to us that the Jews are under a fatal predestination, remaining in Judaism, never to be saved. But God does not see it that way: the Jewish people will be saved by the grace of God without any effort on the part of the majority of this people.
For I would not, brethren, that ye should be ignorant of this mystery, lest ye should be wise in your own conceits; that blindness in part is happened to Israel, until the fulness of the Gentiles be come in.
And so all Israel shall be saved: as it is written, There shall come out of Sion the Deliverer, and shall turn away ungodliness from Jacob:
(Romans 11:25,26)
Here too we do not see signs of repentance among the Jews: simply “the full number of Gentiles” enters somewhere, and after that suddenly all of Israel is saved.
In Daniel, "he" refers to the week itself. The covenant with God was and is, but the covenant will become firm for those who understand the essence of the prophecy about the 70 weeks, and understand how this will now be realized in the construction of the Third Temple and the appearance there of the messengers of Christ from the nations.