He should get it imo. He should have used "the sight" before letting loose *shrug*. The fact is he acted without knowledge, which could have been easly obtained and isn't an excuse. If I was running and the player made this mistake, I "might" retcon it as the character would not have done it unless he didn't have any other choice. However, when you consider he could have put up a block instead of pasting them well....
It's actually pretty clear if you read through all the laws several times and don't look at just pieces of them. It happened so you get it, intent doesn't factor into it. For example look at Molly, her intent was good and was to help them, it wasn't to turn them into crazy people. However, when you break one of the laws your soul is tainted with whatever you did, otherwise it wouldn't be able to be noticed by others through a soul gaze.
So in summary yes it sucks, but that 1 refresh is also the main balancing point of playing a wizard in this game. And if he takes the doom, remember his mentor is also putting his life on the line. That is why it's so rare, most folks won't put thier life on the line for someone else. Another option is that everyone keeps it hush hush and makes sure the council never finds out.