Daboll likely has a ton of input into the personnel decisions. He also probably lobbied hard to give that stupid contract to Jones. And since Jones' $35.5M salary is fully guaranteed, he's not going anywhere. But the worst part is that the best QB prospects, and there aren't a ton to begin with, will be gone within the first 3 picks. Unless they get lucky and find a gem.
The problem is that Daboll got the job largely because of the part people thought he had in making Josh a great QB and thought he could do the same with Jones. But Jones was always going to be what he had already shown and sticking with him, much less giving him that deal, was dumb. And developing Jones, or the lack thereof, is on Daboll.
He certainly helped Josh but the main reason Josh is great is because of Josh and the work he put in to better his throwing mechanics.