More likely, the MSM propaganda outlets realize that most of the public already distrusts Hillary as a corrupt liar. Most of the rest know/acknowledge she is a corrupt liar but back her anyway. So the MSM lapdogs are trying their best to simply not have "Hillary" and "corruption" out there together anywhere since it is already a bad, yet fairly solid association.
I just did another check on Google (for the keywords “Hillary corruption” and found the first reference to the Trump tweet at position 15. The originator? This Free Republic thread.
So I guess the tweet turned out sweet for the FReep!