If you have all of the photos, then you could use a tool like Immich Go, which would automate much of the tagging and album creation. I don’t know if Immich Go accounts for metadata from Synology. However, Synology might be able to export everything.

I would also recommend putting Immich remote access behind Tailscale (I.e., pointing the remove access server to your tailnet and using that domain name and the Immich port to login).

But what if you’re out of stew then? Eat plain injera?