He owed Preibus allot for shutting down 'actual voting' and microphones at the Convention, thus silencing the Conservative movement, what little of it was left after they tasted the 'populist' koolaid.
I don't remember shutting down of microphones (but in all candor, I wasn't able to watch the convention from gavel to gavel).
I think it's more likely that Preibus proved his worth as an effective bridge between candidate Trump and the House leadership (the Ryan wing)---a talent that would be needed as the campaign transitioned to governing.
Preibus was also effective in helping to contain the uprising of a certain wing of the Republican Party (the "p" revolt) after Trump's nomination.
Agree with him or not, Preibus was loyal against stiff opposition and a great help to the Trump campaign.