I did a quick google search of the name Father Rolf Hermann Lingen and the only results I could find were his connection to the free Dr. Fredrick Toben movement. Could it be that he was sentenced to jail for holocaust denial and not because he's a sede? The crime of holocaust denial makes more sense to me especially since this priest resides in Germany.
I believe that because he does not accept Vatican 2...the essence BEING Nostra Aetate, which affirms that Jews ARE God's Chosen people ( A Departure of 2000 years of Church & Council teaching).
This is why he is targeted.
The Mass, while the focal point OF Catholicism, is not the issue (IMHO) here.
Nostra Aetate IS. And why he is targeted.
Sedes are growing ,exponantially.
The Church is having to sell off and close Catholic churches all over Europe due to lack of attendence.
They have 2 choices:
1. Sell the buildings to Muslims
2. Sell to Sedevacantists, and they are choosing the latter.
And that is part of why its growing. People feel the connection to the past, to the Mass and sacraments.