The senate committee is outside of his control. He can install leaders of various agencies who might try to squash investigations I suppose, but even then I think they're beholden to the senate committee. And of course we'll still have tons of journalists and many foreign governments continuing their own investigations.
Unless he starts purges of civil employees in the IC, it will still come out. He can't possibly purge everyone, it will just piss them off and it will still come out.