I get the conflict about morals/justice that they are trying to convey but it bugs me that they also have absolutely no qualms about immediately burning the research. The research could have been used as evidence! I doubt her parents are going to sit quietly about linking their family name to her research. I mean the zombies turned to dust after being purified and the only other testimony is a corrupted noble looking for an out.
I get that the research is dangerous, especially in the wrong hands, but there could have been some useful and non-torture/gore based information.
Like:
1) devising counter necromancer measures.
2) Medical research pertaining to anatomy. (like an autopsy)
3) How she may have solved problems, or made discoveries, in her research that could applied to other fields.
They could have given the research someone respectable, trustworthy, and discrete to analyze it.