A lead investigator in the NFL’s domestic-violence probe of Dallas Cowboys star Ezekiel Elliott produced an internal memo in which she laid out inconsistent statements and credibility concerns regarding Elliott’s accuser Tiffany Thompson, a league source told Yahoo Sports.

That memo, produced by league director of investigations Kia Wright Roberts following her interviews with Thompson, became a significant battleground in Elliott’s appeal of a six-game suspension this week in New York. Testimony from Roberts and NFL senior vice president of investigations Lisa Friel produced key material that will ultimately be weighed by arbitrator Harold Henderson, the source said. Among that material, according to the league source:

• Roberts testified that she was the only NFL investigator to conduct a handful of interviews with Thompson and subsequently raised concerns about those interviews in a memo titled “Tiffany Thompson Inconsistency Transcripts.” Following the production of that internal memo, she recommended no suspension for Elliott.

• Roberts further testified that she wasn’t asked to attend a meeting with NFL commissioner Roger Goodell, when Friel met with Goodell and NFL executives to discuss the findings against Elliott. It was at this meeting – with Roberts not in attendance – that Friel recommended a six-game suspension of Elliott. This piece of Roberts’ testimony was also reported by the Fort Worth Star-Telegram Thursday night.

• Friel testified that she had indeed been made aware of Roberts’ concerns regarding Thompson, including the memo Roberts produced outlining inconsistencies in interviews. She also testified that Roberts was not asked to attend the meeting with Goodell in which Friel recommended the suspension.

Asked if the testimony of Roberts weakened the NFL’s case against Elliott, the league source said: “It speaks for itself.”

The testimony speaks to what sources close to Elliott previously told Yahoo Sports – that his appeal would be formed around the basis of Thompson’s credibility and motives. With Henderson denying a request to compel Thompson to appear for cross examination by Elliott’s legal team, a source close to the running back said the information and assessments produced by Roberts and Friel became a focal point of the appeal. The league source said that focus ultimately led to the revelations of credibility concerns from Roberts. Whether that ultimately undermines the NFL’s six-game suspension remains to be seen.

Should Henderson uphold all or a portion of the NFL’s suspension, the NFL players union preemptively filed a restraining order in Texas on Thursday seeking to set aside any decision from Henderson. As part of that preemptive strike, the union filed a lawsuit in U.S. District Court in the Eastern District of Texas, alleging the NFL committed multiple CBA violations, including hiding evidence that would exonerate Elliott in his case.

Elliott’s appeal before Henderson spanned three days and concluded Thursday afternoon. ESPN’s Adam Schefter previously reported that sources said Henderson “is under pressure” to have a decision on the appeal by Monday. Yahoo Sports reported that if Elliott’s appeal is unsuccessful, plans are in place to fight the NFL in federal court via perceived collective-bargaining violations.

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