The Benghazi Select Committee, chaired by Rep. Trey Gowdy, has formally requested that Hillary Clinton turn over the private server she used to keep under her control all of her communications while secretary of state. That assumes that the server hasn’t been reduced to subatomic particles by now.

Thankfully, the server isn’t the only route to getting to the central reasons why Mrs. Clinton kept total control of all of her communications. Mr. Gowdy may also subpoena actual human beings to testify under oath, including two shadowy figures who may, in fact, hold a key to the story.

Last week this column asked, “Was Hillary Clinton running her own rogue intelligence operation?” It suggested that while secretary, Mrs. Clinton may have been given highly sensitive national security information by the Clintons’ longtime political hatchet man, Sidney Blumenthal. In 2013, the Romanian hacker Guccifer had allegedly breached Mr. Blumenthal’s email account, revealing what Guccifer claimed was a series of emails from Mr. Blumenthal to Mrs. Clinton’s private account concerning global hot spots.

Some of Mr. Blumenthal’s emails to her, assuming they’re authentic, included all-cap warnings such as, “THE FOLLOWING INFORMATION COMES FROM EXTREMELY SENSITIVE SOURCES … .” Many carried a note on the sources of intelligence included in the email. For example, one email identified “Sources with access to the highest levels of the Muslim Brotherhood in Egypt, the leadership of the Armed Forces, and Western Intelligence, diplomatic, and security services.” Another on “Libya internal government discussion” indicated “Sources with direct access to the Libyan National Government.”

The hacked information is silent on whether the intelligence allegedly gathered by Mr. Blumenthal was done at Mrs. Clinton’s request, and it does not show any responses from Mrs. Clinton.

If the hacked information is real, why and how was Mr. Blumenthal so deeply involved in high-level security matters?

The answer may involve Tyler Drumheller.

In 2001 and 2002, Mr. Drumheller served as European Division chief at the CIA’s Directorate of Operations, where he was a highly controversial figure whose disinformation campaigns often landed him in hot water. As investigative journalist Kenneth Timmerman has pointed out, Mr. Drumheller was at the center of the Niger uranium story later used by the left and the press to claim that President George W. Bush had “lied” about Saddam Hussein’s possession of weapons of mass destruction (WMD). “On three separate occasions,” Mr. Timmerman wrote, “he passed the Niger information up the food chain as validated intelligence, when the CIA had been warned that it was not.”

On Sept. 6, 2007, Mr. Blumenthal published a column at Salon.com in which he cited an April 2006 “60 Minutes” interview with Mr. Drumheller, who claimed that the CIA had received “documentary intelligence” from Saddam’s foreign minister that he did not have WMD. In his column, Mr. Blumenthal stated “two former senior CIA officers have confirmed Drumheller’s account to me,” leading Mr. Blumenthal to accuse Mr. Bush of “lying.”

It appears that Mr. Drumheller and Mr. Blumenthal were simpatico, at least regarding criticism of pre-war intelligence. Was that, in fact, the start of a mutually beneficial relationship? After leaving the CIA, Mr. Drumheller advised John Kerry’s 2004 presidential campaign; three years later, he and Mr. Blumenthalworked on Hillary Clinton’s presidential campaign.

In the days before she was sworn in as secretary, Mrs. Clinton told the White House she wanted Mr. Blumenthal in a top official State Department role. President Obama specifically denied her request.

In light of that, the Blumenthal-Drumheller connection raises a new set of unanswered questions:

Did Mr. Blumenthal then team up with Mr. Drumheller to create their own intelligence-gathering operation? Mr. Drumheller has been known to claim he has a global intelligence network of sources and operatives. Does he? And if so, is Mr. Blumenthal in business with him?

If such a partnership exists, was Mrs. Clinton a client? With what countries and sources did they deal? Given Mr. Drumheller’s sketchy reputation, was he properly vetted? Was the intelligence being passed to her — if any was being passed — reliable? Or might she have been a victim of disinformation, perhaps on Benghazi and other matters? If he did pass intelligence to her, did she then share it with the CIA and others?

If this rogue operation were in effect, was it on Mrs. Clinton’s orders? Or perhaps was it at Mr. Obama’s behest, to get them both maximum intelligence they could not get through standard channels? The alleged involvement of Mr. Blumenthal might make that unlikely, but no one really knows.