A little background on Mario Lucia/Sioux Falls: Sioux Falls held his USHL rights. However, about a year and a half ago, Craig Sarner, a U of M alum who worked for Sioux Falls' front office (he was, I believe, Sioux Falls' director of player personnel) was very active in a group of former Gopher hockey players that was trying to get Don Lucia fired. You can guess from this that it might have been just a bit uncomfortable for Mario to go play there, and the conventional wisdom is that this is why Mario left Sioux Falls and chose to play in Penticton.
Also worth keeping in mind, as far as Mario not going to the U of M, is that the general belief is that Tony Lucia's time playing for his dad at the U wasn't that pleasant in some ways, with rumors swirling of jealousy in the locker room and whispers among ill-informed fans about favoritism. I have no idea what actually happened, and think Tony Lucia fully deserved to be there (he was the least of the team's problems in those seasons), but this might have played a part in Mario thinking it was best to play elsewhere.