Thank you everybody for the help. I figured out what I was doing wrong, cause by lack of experience and some dunderheadedness.
First I did not have auto-import looking at the right directories. So I pointed auto-import to the directories with the files on my server.
More basic, I lost sight of where the files actually are. The files are on my server, I was working from a client computer. I went to "Drives and Devices" on the client computer to change the file names on the server. Having corrected the auto-import setting, the library on the server was updating just fine. I had to sync the library on the server to the one on the client, and all was well.
Not being one to pussyfoot around, I then dumped about 20 GB of new files onto the server, and the library updated perfectly.
Thanks for the help, and your patience with a new guy trying to figure it all out.