there is no point in this argument
if she hadn't reverted Tuvix back to being Neelix and Tuvok there would probably be just as much arguing about her still being a murderer for letting Neelix and Tuvok die. This is a no win situation
How would a charge of murdering Neelix and Tuvok work?
What action did she perform that resulted in her personallykilling them did she shot them with a phaser, turn off the life-support? Last I checked failling to act unless you had a duty of care to do so would not result in a murder charge. Starfleet's primary mission is to seek out new life not to exterminate it.
The Transporter can like any bit of technology fail, and surely those that use it accept the risk that it might malfunction when they are in transit and they could be lost. So Tuvok and Neelix accept the risk and with that the consequences.