Okay, I own this. This is my error. I had wrongly believed that Carl-Eric Reintmann had simply disagreed with how his testimony had been discussed in the JAIC report. I had forgotten that he was the one who claimed that the testimony as recorded by JAIC did not match what he recalled having said. You're mostly right on this point, and I'm mostly wrong. I agree with the point you're trying to make. If the investigators record something different than what the testimony actually was, that's very wrong, very unethical if done intentionally, sloppy if accidental, and probably legally actionable if an injured party can prove it.
This is very different from the witnesses of TWA 800. We have transcripts of their statements and their interviews. To my knowledge, none has ever claimed that these records of their evidence are in error. Many claimed they saw a missile hit the airliner. But that is not really what they can testify to having seen. They saw things that they concluded were consistent with their understanding of how a missile looks when flying. The analysts then have to determine what other things are also consistent with those observations, and determine how likely those are in comparison with an actual missile, considering the totality of different kinds of evidence. the final report may end up disagreeing with what the witnesses' believe they saw, and this may distress them.
Based on what I read
here it seems that there are simply two different versions attributed to Reintmann. He didn't read his statement in writing in the JAIC report until six years later, whereupon then he claims to have remembered it differently. And in 2020 he's giving interviews to that effect to newspapers wherein he also buys into the submarine-collision theory favored by the shipyard trying to clear its name.
How do we know his dispute with the JAIC report isn't later revisionism? Can he provide any evidence that he gave a different report to JAIC interviewers at the time than what they recorded? And no, you don't get to start with the presumption that JAIC is evil. You're citing this witness's experience as evidence that the JAIC work was biased, so it's circular to assume that as a premise.