I'm rebuilding the wiki index right now. During this process, the complete ToH data will be re-read from the dataentries into the database. Hopefully this fixes it.
Re-indexing will take some time, I expect 1..2 hours.
Please mind that during this time, the wiki search function will not work as expected due to searchindex-rebuilding.
There was a lot more going on than just that. I've documented things somewhat. I'll try to clean that up and put it somewhere. For now, people with access to the server have access to my raw notes.
Intermediate status:
Fixed some issues in the meantime.
We are on the right track. indexer is still running, but I see the previously missing data appear in the ToH as the indexer progresses. ToH should be fully working again in 15..30min or so.
EDIT: Indexer has finished, all missing data is now shown AFAICS, ToH is working again.
Should you still observe issues with the ToH, please report here.