First, the Council of Trent at the At the eighteenth session (25 Feb., 1562) offered safe-conduct for Protestants. This was so they could come before the Council Fathers, and explain their doctrines, after they where given a guarentee of safe conduct home. Luther and the other Protestants refused. It had taken more than ten years up to that point, Protestant princes and the Emperor had squabbled over where the Council should be held, and postponed the opening of the Council, prevented bishops from travelling to attend the Council. Many of the princes who initally accepted the Protestant “reformers” saw it as a way to gain control over the land and posessions of the Church.

As far as Vatican II and the teachings on Orthodoxy and Protestants, we have to look at what the two Councils where called into being for. Trent delt primarily with Doctrinal Matters, ie was something an authentic Catholic teaching or was it a heretical teaching that contradicted what the Church had always taught. There where some pastoral issues, such as the problems with the training, educational and spiritual of the parish clergy.

Vatican II was primarily a Pastoral Council. This does not mean as some assume that it can be ignored.

Since the Councils where looking at different things their documents look at the issues from different points of view. However if we look at Trent, while it (and later decisions of the Church) condemn the new doctrines of the Protestants as heretical, they do hold that the baptisms of most all the Protestants are valid, or true sacramental baptism. So Protestants are truly baptized, and as there is only one Baptism, (you are either baptized or you are not) they are members of the Church, however because they deny many essential teachings of the Church they are imperfectly connected to the Church.

Further, the Church devided an individual between a Formal and Material heretic. A formal heretic would be someone like Martin Luther, who knows what they Church teaches and rejects it outright. Material heresy is a matter of error that is not culpably held: it is to hold to an error without knowing better, or without realizing that it is an error. So someone who rejects the teachings of the Catholic Church because he is raised outside of the Church, or does not have the chance to learn what the Church teaches, cannot be held at fault for not ascenting to all the Church teaches. The Catholic Church holds that God will judge people based on what they know and understand. At the same time if someone had the chance to learn the Truth, and rejected that chance, God will hold him culpable for that too. We as humans cannot see into the soul, and therefore cannot condemn them, only the errors they hold.

So I would say, yes Vatican II upholds what Trent says, but Trent tells us what is heretical and what is not. Vatican II tells us (more clearly) how to deal with persons who are separated from full communion with the Body of Christ.