Sync to New Server from Client

My NextCloud server and data runs on a host that died. I built a new host and moved the server over, but the data drives were not recoverable. The desktop that I run the nextcloud client on still had all the files. I put new, empty data storage on the nextcloud server. The idea was that the client would show new files and sync them over to the server, rebuilding my data. Since it wasn’t a new install, either the client or server believed it had already sync’d the older files, so it began syncing new ones. After that, it appears to continue syncing the old files, but many are not and I am getting 409 and 404 errors (server replied 404 not found to PUT) for several files. The sync appears to be continuing in the background (I see heavy network traffic to nextcloud, and when running ‘occ files:scan --all’ the number of folders and files continues to grow, but I have no indication of what is really happening (could be that I don’t know where to look for correct logging).
Is there a way to tell the client and server to purge their memory of files and get a ‘fresh look’ at what files are on the server and the client, and then it can sync the files from the client to the server data properly?

I think I resolved most of the 409 errors by copying that directory out of Nextcloud area, deleting it from the nextcloud area, then copying back in. But this may not work for all of the files since I don’t know where many of the ones that are not syncing are, and I would rather not change the timestamps on all of the files since those dates are needed.

Using the Explorer indicators, I robocopied all the non-syncing directories out, deleted them, then robocopied back in. This preserved timestamps. For some reason, nextcloud decided one of my directories, and all sub-directories and files, should be deleted from the client instead of synchronized to the server. I’m REALLY hoping at this point it didn’t do that to other files/folders since the only reason I saw this was an error that it couldn’t delete one of the folders.