author of the bucket and history-publishing subsystems here!
It does sound like the root cause is intertwined with the backing-up history publishing queue. There's a chance this has to do with configuration on your side, so I'd be curious if you could share a log of the publish failures and/or the history archive configuration lines from your stellar-core....
Without access to your private network it can be a little tricky to debug.
This seems likely to be a problem with a corrupt bucket file, which can happen if there's an error or data loss during XDR IO. Bucket files are kept on the node's local disk as well as being published to archives. In versions before 11.4 we failed to call fsync() properly during ...
Experience now allows me to update this answer for googlers of the future. When running Stellar Core in Docker you must persist the following:
Set BUCKET_DIR_PATH in your stellar-core.cfg and persist this location outside of the container
If you put to a local history archive also ensure this location is persisted outside of the container