Complex sentence: The president of the assembly insisted "one has the right to refrain, but not to object to the wishes of the congregation" but in spite of this, Martin-Dauch wrote "opponent" in front of his name.
Split into simpler sentences: The president of the assembly tried to convince Martin-Dauch that members had the right to refrain, but not to object to the wishes of the overall congregation. In spite of all of this, Martin-Dauch stood firm and wrote "opponent" in front of his name.