I'd rather have the prospects that Villar and Mancini will return than those players themselves. I also don' t thin the O's are interested in putting the best team possible on the field in 2020.
As Elias has said on numerous occasions, next year is not about wins and losses. And as he explained when he was hired, his goal is not necessarily to get back to contention as quickly as possible, but to develop a pipeline of players that will continuously feed the major league team for years to come. We aren't there yet.
So, as you put it, "what Elias needs to do" is keep players in the minors until there is nothing more for them to gain from being there. What happens at the major league level is of tangential interest- he doesn't want them to stink the place out while they lose 100 games. If he can find a young, undervalued ML player at minimum, he'll be glad to give him an opportunity to prove himself.