I asked if there could be a glitch with the cable box itself, and was told that because we are able to rent regular movies that there can't be anything wrong with the box.
Sounds it was a porno. Practice your sternest voice and go ask your husband again. There used to be a way to spoof a settop box and receive unsubscribed multicast channels but that hasn't worked since their network was upgraded. As far as I know, there has never been a way to get free VOD movies without exploiting humans rather than technology.
 In other words, watch the movie and dispute the charge when the bill comes. Keep disputing the charge until the other side gives up because eating the cost of the movie is cheaper than arguing with you. Back when I worked in a hotel, we would comp just about any disputed charge without argument but I suspect Sasktel (or any other TV provider) doesn't need to be as forgiving.