All right. I'd be glad to answer all your questions.
As far as third parties are concerned, under the current criminal law regime, anyone who helps a sex worker practise is considered a pimp, or procurer. Therefore, if I work with a friend, one of us could be considered the other's pimp. A driver or receptionist could also be considered a procurer. Basically, under the definition of procuring, anyone who contributes to our work is considered a criminal, even if they aren't earning any money. Benefiting financially from sex work is a separate criminal offence.
Of course, third parties tend to be people who are very helpful in the practice of our work. Thanks to them, we can implement all kinds of safety measures and establish a dynamic where we have more power over clients and would-be attackers. They see that we are protected and that someone will know if anything happens to us.
In Marylène Levesque's case, I think the perpetrator was very aware of how important it was to her that no one at the hotel realize she was a sex worker. All kinds of things could have happened. For example, if she was naked, would she risk running out into the hall and being found out, only to realize that the situation wasn't as dangerous as she had thought? Those factors make a big difference.
As for how many former inmates see sex workers, it's impossible to know. There aren't any statistics on that. Keep in mind that people from all walks of life and every occupation see sex workers for a variety of reasons. Parliamentarians are just as likely as former inmates to seek out sexual services, in a wide range of circumstances. What's more, those circumstances tend not to revolve around exploitation or violence.