Both are in the fort itself, in the "re-education" area, the floor of the fort between the prison cells and the courtroom kinda thing. You can get there from the prison level if you have someone with lockpicking ability (I forget offhand if the main door out of the cells is level 1 or 2) which avoids a confrontation with the houndmaster and his men. That floor also gives access to the area where Withermoore's soul jar is kept.
I'm not sure if fighting the dogs or killing the silent monks turns the magisters hostile, so save before doing anything...
