It was pretty evident to me that Schumer clammed up after the WH visit. But Adam Schiff was more combative; hard to find an exact point. I don't think it was the liddlekidz drop; maybe around the time of the helicopter crash with the former manager of the Standard Hotel? I don't think he even quieted down after Q revealed they'd traced his phone call yo Valerie Jarret, through 12 nodes (I think). If we can track that moment, it would be telling.
To me, the Schumer one is proof-worthy. One caveat, though; polls showed that people were blaming the shutdown on the dems, so that could be used to explain things away.