Idk I wouldn't trust it they usually leave back doors. I got an old ransomware in like 2011 and did what you said above, It worked initially but was never the same, wound up trashing the computer.
For the school we had to do all kinds of craziness, including replacing about 25% of their servers, and then finding out later that they had gotten into about 50% of them and laid traps, but I am in more of an overlord role than a nerd at the keyboard role.
All I'll say is I would not be comfortable with the actions you have taken so far, if I was in your shoes. I have not dealt with egregor before and deal with this stuff at more of a corporate level than a personal level, so feel free to ignore my paranoia.
