They forgot to mention his 2 felony convictions.
(a) General Rule. For the purpose of attacking the credibility of a witness, evidence that the witness has been convicted of a crime or an attempt of a crime must be admitted but only if the crime committed or attempted is (1) murder, treason, rape, robbery, kidnapping, burglary, arson, or criminal confinement; or (2) a crime involving dishonesty or false statement, including perjury.
The use of false name and theft convictions are both considered crimes of dishonesty. In other words, to most objective prosecutors, this guy is radioactive and they don't want him near the witness stand. Particularly since his version has been completely discredited by the autopsy report.