I've heard once or twice from other people with your problem. I figured that they never selected a candidate for promotion or hadn't finished all three parts of the quest. Maybe I was wrong. Since you are absolutely sure that you did those things, I guess you've found a rare bug.The Minisaves have nothing to do with promotions so you can stop wasting your time with them. They only define the layout of the landscape. Everything important about your game is stored in the savegame.HDR file.
You have three options now
1) reload a save game and talk to the Green Man again.
2) become a Priest instead. They're better anyway.
3) use a hexeditor to modify your savedgame.HDR file and make yourself a Druid or reset the quest.
