The goal with any Congress is to think what if the parties were reversed. Would the conversation be the same if Hank "[Guam] the island will tip over" Johnson asked for information on the collusion between an agency and outside agencies.
We have a government agency turning down a request by a voted in member representing the populace of the United States of America that elected him. There is no reason for a government agency to be doing this. They should be accorded the respect of the position, no matter how much someone disagrees with it.
We have a situation where the Republicans postulated that the IRS was coordinating against a group of individuals to prevent their recognition during an election, and were proven correct despite agency stonewalling. The agency head had a secret e-mail to avoid FOIA, so searching for a slip-up required going through thousands of e-mails.
Another agency had its Secretary running a private server as an end run around the FOIA. Where upon closer inspection reveals that the agency publicly deceived the populace on originations of a terrorist attack.
Additionally, the federal government has been on a bender with coordinating against individuals in the name of political purposes. Witness former Senator Stevens railroading, IRS' Lois Lerner, and EPA's Phillip North coordinating with EPA on Pebble Mine.