Sorry for the lack of feedback. Work this week has been....tough. To avoid repeating myself I'll go by topic.
This Save Game: As I mentioned, depending on if I take out a bracket or not, I can either have the game fail to load at all, or have a no government/no ruler nation.
I took Ragusa's advice and let it try to play out, thinking I could explain a new ruler away as a coup. I did indeed get a new ruler - but still no government. In addition I lost all my accepted cultures, and the game thinks it's 1419, not 1491. (I checked line 1 of the save: The save file year is correct. It's loading wrong.)
I threw it into comagossie's save game editor. It loads there just fine, but it won't load in game. That made me suspicious, so I tried starting a fresh game. That worked, so it's definitely in the save file. Somewhere.
Changing Names: Wolfcity asked why I had to edit the Hochmeisters' names in: In EU3, theocratic leaders are treated like kings with Roman numerals following their names, so George III might be followed by Edward II, George IV or Francis IX. That works great for the Papacy, but not so well for the Teutons, who didn't track their Hochmeisters in this manner.
I checked more than once: I inserted Egan's name correctly. I did check other parts of the save, though I forget exactly what and it was only to satisfy curiosity. Obviously something went wrong.
Going to the Autosave: Tried that. Exact same thing happened. The autosave loaded. I brought it forward from March 1491 - December, killed off Sangerhausen, and made sure I made the same decisions as before. Something....happened within those nine months, and apparently it has nothing to do with my looking around the old save fil. I've played around a little bit (ripped out Danzig's grain depot, etc., changed the Hochmeister's name back) with no effect.
I think I'm going to take this as divine intervention. One Teuton crash is a shame. Two Teuton crashes is bad luck. Three is a signal from the gaming gods.
The Future: There will certainly be another AAR - perhaps here, perhaps CK (I don't own Vic anymore, and AoD leaves me as puzzled as HoI2 did. FtG I suppose is a possibility.) With what country and in what format I'm still chewing on. Lithuania would be an amusing possibility after trying so many times to beat them up
Thanks everyone.