Thank you for your question.
The word translated watcher(s) occurs just 3 times in the Aramaic section of Daniel.
Daniel 4:13 I saw in the visions of my head upon my bed, and, behold, a watcher and (or even) an holy one came down from heaven;
Daniel 4:17 This matter is by the decree of the watchers, and the demand by the word of the holy ones: to the intent that the living may know that the most High ruleth in the kingdom of men, and giveth it to whomsoever he will, and setteth up over it the basest of men.
Daniel 4:23 And whereas the king saw a watcher and (or even) an holy one coming down from heaven, and saying, Hew the tree down, and destroy it; yet leave the stump of the roots thereof in the earth, even with a band of iron and brass, in the tender grass of the field; and let it be wet with the dew of heaven, and let his portion be with the beasts of the field, till seven times pass over him;
Using Strong’s Concordance.
Watcher 05894 (Aramaic) eer; from a root corresponding to 05782 (to rouse oneself, awake, awaken).
Translated in the AV-watcher 3 times.
Meaning: waking, watchful, wakeful one, watcher.
It is reasonable to conclude from the available information that ‘watcher’ refers to an angel.
We understand from scripture that everything God does is done by the hand of angels.
Angels watch over and preserve the righteous.
Psalms 34:7 The angel of the LORD encampeth round about them that fear him, and delivereth them.
Acts 12:11 And when Peter was come to himself, he said, Now I know of a surety, that the Lord hath sent his angel, and hath delivered me out of the hand of Herod, and from all the expectation of the people of the Jews.
Hebrews 1:14 Are they not all ministering spirits, sent forth to minister for them who shall be heirs of salvation?
Angels are the instruments of punishment when required.
2 Samuel 24:16 And when the angel stretched out his hand upon Jerusalem to destroy it, the LORD repented him of the evil, and said to the angel that destroyed the people, It is enough: stay now thine hand. And the angel of the LORD was by the threshingplace of Araunah the Jebusite.
2 Kings 19:35 And it came to pass that night, that the angel of the LORD went out, and smote in the camp of the Assyrians an hundred fourscore and five thousand: and when they arose early in the morning, behold, they were all dead corpses.
Acts 12:23 And immediately the angel of the Lord smote him, because he gave not God the glory: and he was eaten of worms, and gave up the ghost.
God is everywhere present by his spirit. He is aware of everything that happens before it happens.
We do not understand the relationship between the angels of God and the spirit of God.
The point that God is making through the angel with Nebuchadnezzar is clearly stated.
Daniel 4:17 ...to the intent that the living may know that the most High ruleth in the kingdom of men, and giveth it to whomsoever he will, and setteth up over it the basest of men.
This is still not generally understood in the world.
To this day ‘Christians’ are involved in politics.
What part of Daniel 4:17 do ‘Christians’ not understand?
A small insight into angelic influence behind the political scenes is given in Daniel 10.
Daniel 10:13 But the prince of the kingdom of Persia withstood me one and twenty days: but, lo, Michael, one of the chief princes, came to help me; and I remained there with the kings of Persia.
20 Then said he, Knowest thou wherefore I come unto thee? and now will I return to fight with the prince of Persia: and when I am gone forth, lo, the prince of Grecia shall come.
Here we see the angels working with the freewill of the rulers of Persia and Greece to bring about the demise of the Persian empire and the rise of the Greek empire.
Again we don’t know how angels work in the lives of men but it is clear that they do.
Angels are closely connected with our salvation.
Luke 15:10 Likewise, I say unto you, there is joy in the presence of the angels of God over one sinner that repenteth.
Luke 12:8 Also I say unto you, Whosoever shall confess me before men, him shall the Son of man also confess before the angels of God:
The promise of God is that those who obey the gospel will be made equal to the angels.
Luke 20:35 But they which shall be accounted worthy to obtain that world, and the resurrection from the dead, neither marry, nor are given in marriage:
36 Neither can they die any more: for they are equal unto the angels; and are the children of God, being the children of the resurrection.
I hope this helps.