What the real problem is is that the TLA agencies don't have anything to lose with this.

Is there no way to go: "All right. We'll do that. HOWEVER, if we don't find anything on this phone, we want this held up as a prime example of government overreach and we want all further attempts on this judicially banned."

If the TLA agencies had a downside to losing the case, they'd drop it in a flash.