Lots of things could have happened for Tony LaCava to decline signing with the Orioles. Highly talented people sometimes don't take good jobs (see Rick Hahn or Billy Beane). I think it might be presumptuous to say it had to do with limitations placed by Angelos on him. Frankly, we do not know and it does not really matter. If Angelos is a problem, he is a constant. He will not change, so we must focus on the part of the team that can change.
So what is the problem with Tony LaCava's decision?
It resets the interview process with two days to free agency. DeJon Watson and John Stockstill will not be given a fair shake by the press or the public as the best options. Watson will likely be seen as the third choice and, perhaps unfairly, Stockstill might be seen as a placeholder. In this light, the team has to interview at least two more people and that will set the clock back another week. The organization was already going to go through some pains through transition and this delays that further.
At some point, it might actually be best for Buck to take a year off from the dugout and try being a General Manager. I don't think that is best for the Orioles in the long run. However, if they want to move quickly in free agency they need to start getting their plan in order. That might mean continuity.
So again, the issue today is not that LaCava is not coming here. There are several GM candidates in baseball who have as good potential as he does. The issue is that the front office remains unsettled while everyone else is ready to enter the off season.