Mods are not downloaded, "Timed out waiting for AppInfo update..."

[MadMaxMcKinney]

Running this docker container on a DS1019+ Synology NAS for context, but I can't seem to get the mod fetching to work. The server downloaded dotnet stuff, tModLoader updates, etc and functions "normally" letting me join it but the logs are showing errors around downloading the mods.

steamcmd has been disconnected from steam with result 3 (No Connection)

There are some more errors about not finding those mods in the expected locations (cause I'm assuming they didn't download). Any ideas? I'm using the Calamity mod IDs from the example docs but I also double-checked they are still the correct IDs.