Yeah, that's been a curiosity. When he was first hired here, he issued a strong warning to the press to leave his family out of it. IIRC, he did talk briefly about when his first child was born but that's it.
Couldl be his wife simply wants to remain out of the limelight, which is completely understandable.
I don't know the 'why's' either, but it could be exactly what you're saying.
Once they're brought into the conversation, they're part of the conversation and not easily removed. I don't think Nebraska's media would have done anything untoward regarding his wife, but setting the rules up that way does change things.