After reading a number of posts concerning the shit-dom of interlaced VC-1 encoded movies I finally met my own nemesis: Election 2. Whatever I did in the first place, it just wouldn't work. So here's my workaround. It was awfully time-consuming. But in the end I was rid of doo-dee-1 and had the movie ready for further processing. Here goes:

1. open the disc with tsMuxer, select the features to keep and remux to a new Bluray structure
2. check the size of the remux and open it with BDRebuilder
3. adjust settings to keep audio and subs untouched
4. set the target size to custom: sizeof(remuxed structure) minus 10 MBytes
5. set BDRebuilder to deinterlace the source
6. encode the remux to a brandnew Bluray structure, now without doo-dee-1
7. do whatever you want with your final encode

This took me quite some time and disc space, but for that movie it was the only way that worked.