[2.0.13] "Core mod CRC check failed! ..." while connecting to Multiplayer Server

[safetyguy14]

While trying to connect to a locally hosted dedicated multiplayer server, all users get the following error:
"Core mod CRC check failed! Core game data does not match expected content."

Server was operating on version 2.0.11 without issue as of this morning. Server was updated to 2.0.13 so all users also updated their clients to 2.0.13 and have been unable to connect since.

Have tried verifying files and reinstalling the game a on steam client-based machines.

Log file and screenshot of client provided.

Relevant parts of server log below:

16680.982 ConnectionRequestReplyConfirm (type(ConnectionRequestReplyConfirm) ) from(IP ADDR:({redacted}))
16680.982 Refusing connection for address (IP ADDR:({redacted})), username (safetyguy14). UserVerificationMissing
16681.266 ConnectionRequestReplyConfirm (type(ConnectionRequestReplyConfirm) ) from(IP ADDR:({redacted}))
16681.266 Refusing connection for address (IP ADDR:({redacted})), username (safetyguy14). CoreModMismatch

[StrangePan]

Can you provide the save file that's having trouble? If you have any autosaves from 2.0.11, including one of those too would be good.

[safetyguy14]

I provided the save and the latest autosave, ty

[safetyguy14]

Troubleshooting Update:
I looked at save in singleplayer; it showed all the main mods still being 2.0.11. I then tried opening it; which worked fine. I saved it which then showed all the main mods being 2.0.13. I then exported it back to the server. After a restart it was working as expected.