I fixed the issue!
3 damn days on this!!!
The issue was a corruption somewhere, could be the indexer container, so, what I did is, I recreated the DB, using the following command:
docker compose stop
docker compose run --rm musicbrainz fetch-dump.sh indexed
admin/purge-message-queues
docker compose up -d search
docker compose exec search fetch-backup-archives
docker compose exec search load-backup-archives
docker compose run --rm musicbrainz recreatedb.sh
docker compose up -d
Here is a twist, even after doing this, I discovered I can’t use the indexed search for type recording, I invoked the index rebuild for just that and it worked this time:
docker compose exec indexer python -m sir reindex --entity-type recording