It is an interesting question. I’m a little skeptical of how much should be read into some of these more incremental stories. Every investigative journalist is chasing the Trump-Russia stories. There may be more good stories produced by the intensity of the effort. But, increased competitive pressure may also incentivize a lower bar for reporting.
Priebus is one of the more reasonable figures in Trump’s orbit. He’s a man not given to wildly irresponsible behavior. Consider the possibility that FBI sources previously had assured him that the NY Times story was was not accurate. It would be understandable that he might express frustration that they would not correct the record publicly. The FBI’s refusal may be indicative of policy of not commenting on ongoing investigation rather than tacit confirmation of the allegations.
If there is a conspiracy with regards to the Trump campaign and Russia, its entirely conceivable and perhaps likely that Priebus, who was not on the campaign, would not be read in on it. In which case, his contacts with the FBI although potentially a breech of protocol could be innocent in other respects.