If I understand you correctly
You placed 300 DPI images into an illustrator file at 100%.
Then placed the AI file into InDesign and scaled it up to 4000%.
If that is what you did, then your images will not print at 300 DPI. Putting them into Illustrator doesn't change the fact that the DPI goes down as the scaling goes up.
What you will get with the above workflow is images that output somewhere around 8 DPI.
When you enlarge raster images in InDesign, no matter how they got there, they are not resampled. Your 300 ppi images printed at 4000% will have an effective resolution of 7.5 ppi.