Brea was arrested last Tuesday (23Nov10) and charged with murder after his mum Yannick was found stabbed to death at her New York City apartment.
He hit headlines as the 'Ugly Betty actor' as details of the brutal scene unfolded, and eventually confessed to slaying his mother in a religious sacrifice, insisting he was "doing the work of God".
But the show's second assistant director Jim Nickas is adamant the actor has been too closely tied to Ugly Betty - revealing he worked only as a background extra in one episode of the series in 2009.
Nickas tells the New York Post, "He worked two days on the first episode we filmed (for) Season Four.
"We have 90 background actors the first day and 70 the second day. Some (posing as) restaurant staff, but mostly patrons. So it is pretty lame that the headlines have read: 'Ugly Betty actor Michael Brea.'"
Nickas admits he had "never heard" of Brea before consulting the show's casting records, adding, "He has also been reported as being on Step Up 3D, which is kind of funny because my wife worked on that movie, and she didn't remember him, either."
Mystery surrounding Brea's acting credentials has been growing since a Hollywood trade magazine first reported the story last week (ends26Nov10).