Well, the Seaweed server issue was worse than I realized. Due to a tardy update on my part, somebody seems to have exploited a CVE for SeaweedFS between September & early October, locked out any existing ssh keys, and set up self replicating bugs.
Customer support helped restore access to ssh, and from there I've closed (hopefully) their backdoor long enough to pull a backup of the S3 buckets before I do a clean wipe and reinstall. All credentials will have to be rotated, including ssh keys.
Fortunately, I should be able to get seaweed back up and running without any data lost. What a pain in the ass...