"Sigmund' is the pseudonym that David Wilcock and Corey Goode chose to describe someone in the Air Force (Military Industrial Complex Secret Space Program -- MIC SSP) who abducted Corey and tortured him 12 times! In Season 5: Episode 7, Corey explained that he remembers walking barefoot in the parking lot behind his house with military people around -– walking toward a craft! On the craft, he was strapped into a chair and interrogated. They stuck an IV in his hand to drug him.
"Sigmund" interrogated Corey because he wanted to determine the truth of Corey's reports on the Cosmic Disclosure show and elsewhere. Corey's information was so far beyond anything "Sigmund" had learned in the Air Force that he just couldn't believe it. However, he was finally convinced that Corey is telling the truth. When he was chemically interrogated, Corey inadvertently identified three colleagues in the Secret Space Program. One was killed and another went missing. His friend "Gonzales" can never return to Earth and is now working with the Mayan Healers on their craft to help with their mission.
Corey describes another abduction and interrogation in Season 6: Episode 12. Corey's information was so far beyond anything "Sigmund" had learned in the Air Force that he just couldn't believe it. However, in Season 6: Episode 16 Corey reported that "Sigmund" was finally convinced that Corey is telling the truth.
In Season 5: Episode 7, Corey said the Blue Avians later explained to him that these incidents needed to occur as catalysts for other things to happen.