All of the images are currently on the internal drive and the same images are still on the external hard drives too. I did use lightroom to export the images onto the internal drive but none of the keywords are there.
OK, this is where we need more explanation. 'Exporting' the images shouldn't have come into play.
There were two basic ways you could have accomplished this:
1) Within Lr, simply move the images and their containing folders to the new internal drive.
2)With the OS tools Finder/Explorer you could have made an identical copy of the existing images(the whole folder tree) from the existing external drive, on the new internal drive. Then within Lr, right-click on the top-most folder available, and choose Update Folder Location.... and navigate/point to the new internal drive location.
Before you try anything else, make sure you have a good backup(s) of the *.lrcat file(s). If the image locations on the new internal drive are identically arranged compared to the external drive, you can give method 2 above a shot. You might want to start down low with a small child folder, instead of a top level master folder, just to verify the results, before committing to a wholesale change.
Unfortunately, like Denis, I'm going to be offline for a few days as well, I hope somebody will keep up, in our absence.