Hello Jennie,
 
Jennie if you do a search into the very old translations, such as Ethiopic Bible. You'll find Enoch was included in the Canon at one time. The first 4 centuries of christianity quoted the works of Enoch. It wasn't until the "Sethite view" came in, that Enoch was rejected.
 
As for the "Watchers" the Watchers are not only mentioned in Enoch, but the book of Daniel as well.

Daniel 4:13 I saw in the visions of my head upon my bed, and, behold, a watcher and 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 4:23And whereas the king saw a watcher and 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;