It would only be a “legal out” under this scenario:

The Q Team either is military, or has military components. They have used their expertise and resources to gather evidence of a major crime, and eventually, they conduct mass arrests of numerous civilians, mostly politicians, scientists, industry leaders.

Normally, this case would be under the purview of civilian law enforcement, but as is the common belief, the Q Team, in this scenario, used military resources, and may have had the military conduct the arrests and carry out sentences.

Now, in this scenario, the Q Team had no Congressional authority, and nothing from the Constitution gave the military in Q’s Team authorization to participate in this operation.

And in this scenario, Q’s Team was willing to fall on their sword. Yes, it was illegal for them to build and conduct the case with the military, but they would happily suffer the consequences, because the evidence would exist and back up their prosecutions. They would be legitimized by their evidence, even if it was criminal to obtain.

In this scenario, Schiff’s amendment would fuck them. Because now, it would ensure that if you are a criminal and committed a crime to build a legal case, your evidence is considered invalid.

Essentially, this would stop the evidence from being useable only if the Q team is already convicted of having violated the law in using the military for law enforcement purposes.

If Q did not involve the military, or had Congressional approval for his team, or otherwise did not already violate the law regarding the separation of military from civilian law enforcement, then the Q team cannot be touched by Schiff’s amendment.

I am not a lawyer, but that is my untrained, unprofessional reading of it.

Schiff’s motivation could be as simple as “he’s a lawyer and ensuring criminals can’t commit a legal suicide-bomb by benefiting legally from their crimes.” But that would require the benefit of the doubt, and such things tend to be rare here. :)