Did they send you the images, too? Sounds like they are missing, or not up to date.
I do believe you are correct. They sent me about 1/2 the images. After further investigation, all images they did send are not pixelated in the document. Those missing are.
I'm still fairly new with InDesign Thanks for your feedback.
What gets me is I don't have those images, yet they still show up in the ID and PDF documents. How is that possible?
InDesign creates low resolution previews of placed graphics (to enable quicker screen draws).
When you opened the file you should have been alerted that the document contained missing links.
During the work time on the file, the links panel would have shown similair to
InDesign probably also alerted when you exported to pdf.
If you have instructed InDesign to disable warnings, you should consider turning them back on from the Preferences panel
Edit > Preferences > General