My question is, I need to make an update to a document but don't have the root images. In the past, when updating these documents, the image quality gets fuzzy once I make these changes. Is there a way to save the image quality and not lose the image resolution?
You can embed the original images in the InDesign document rather than link them.
I'm not clear on how you would embed images with broken links. Nor do I think embedding images is a good idea in general as it has the potential to make the file so large it can't be opened and edited.
But more to the point, what you are looking at in theInDesign file is a preview image, and the actual linked image data will be used for output, if it is available. Are you saying the images are no longer available at all, or simply that you don't have access to them but whoever is responsible for final output will?
So I have Indesign documents created by a team that didn't package the document or link them to a folder. When I make a change to the Indesign document the images go to the 'low res' image; when printed in PDF photos are fuzzy.
If you have high-res PDFs of the previous work, you can use Photoshop to extract the images from the old PDF. (File > Open in Photoshop will get you a dialog which will allow you to choose Images)
Obviously the links are broken now, but if you look in the links panel it should show you the old path to the files which might give you a clue where to look on a remote server.