Ah, Adolph Eichmann, God rest his soul, surfaces again in your posts: you seem to have a fixation upon this unfortunate person.
You have culled from Aquinas quotes to bolster your erroneous beliefs regarding conscience. Vatican II speaks also of conscience:-
How then do we form a right conscience? Catholics seek to inform their consciences according to reason and revelation as guided by Church teachings. They believe that by "their faith, aroused and sustained by the Spirit of truth, the People of God, guided by the sacred teaching authority (magisterium), and obeying it, receives not the mere word of human beings, but truly the word of 
God." (Vatican II, The Church (1964), §12)
Do, you reject this teaching of the Vatican Council, I doubt if St Thomas would?
To have an erring conscience can be sinful insofar as the effort to inform it is cursory.
Reading the bottom line is often a way of saying that this is my personal take upon the issue.