He’s not the same person, but he is based on that person. He even has the same ethics in the episode, saying that patient opinions on trearment don’t matter, and almost tortures the other alien to death before the Doctor steps in and stops him and uses a more humane method.
Personally, I have a problem with Janeway forcing the issue on B’Elanna, since it would be like the government forcing me to have a treatment I morally object to. And I object to the Doctor deleting the research, but not the hologram.
I would instead suggest he just replace the research with more ethical tests and then delete it. Otherwise, just keep it locked away and only used in an emergency.