What's important to note is that Mr. Pilfnam had arrived on the scene long before Lizzy did. He was the first person on the scene, and he made it there long before the rest of the police did. It was then, if not from the beginning, that he realized that Kathryn was still alive. He forged a photograph that made it look like she was shot in the head, then sent her to his accomplice, Dr. Lendez, and had him forge an autopsy report. Why? For some unknown reason, he had to make her seem dead, likely a result of the corruption growing in Answell's police department. Lendez himself was either in on it from the beginning or bribed then and there.
Meanwhile, Mendax had himself to worry about; he believed he had killed Kathryn, and he intended to get away with it. He chose to tell nothing but the truth, but not the whole truth - in other words, just tell them Richard did it. This did not work out well: as Pilfnam had not told Lendez the time Kathryn had been shot, he went with the rough time he brought Kathryn to her. This, as well as the faked cause of death, was what tripped Mendax up in court and led to him embarrassing himself.
Adding onto this, although it was Mendax who claimed the gun was in the toilet bowl from the beginning, it was Pilfnam and Lendez who allowed it to be filed into the Court Record - but that was when Mendax's fate had been sealed, for they had planned to use it to make him take the fall. Lendez, who had been given the gun, wiped Richard's prints off the handle, but left the prints on the barrel. The issue of fingerprints existing on the gun even though it was submerged in water would call Mendax's claims into question - and Lendez himself made sure of that by directly telling Lizzy that the prints would've been washed away!
After this, Lendez and Pilfnam likely show up later in the game, and are eventually exposed. Kathryn Davies is either the final killer or the final victim. Whether the three were involved in FemCon is uncertain, but we already have it confirmed that more than one game will be made in the Acquittal series, so it's possible that FemCon won't even be solved in the first game, meaning Lawrence is still clear to be the culprit there.
Finally, SJGriffiths did himself confirm that case 1 would be changed, so clues like the first two testimonies might be different, but to remove entire characters like Lendez and Pilfnam? That much seems unlikely, assuming they really do appear in later cases. Therefore, this could reasonably continue to hold true in the final release.
