I do find it baffling, and I agree that the prison system - like the wider justice system - is running on fumes, and many things including training is barely hanging by a thread. I've seen reports where those in training are meant to learn all their communication skills for their job just by observing others while they work... no overt training.
Some of these may be women who fell for the same performance women outside of the justice system fall for - people starting relationships with people in prison for violent crimes is not unheard of; some of these will intentional for various reasons, many already mentioned.
I would be cautious assuming a woman in authority isn't very able to take advantage of others, including men, particularly when we consider that a significant portion of people in prison have learning disabilities. Some of them can be very manipulative - I've very much seen the switch in an inmate when their mark walks into the room - but when I consider that the prison population includes those that have been deemed not cognitively fit/capable to put in a plea, yeah I can see how someone who wanted targets would be attracted to this type of work and would do the things we're seeing.