In the first one, I agree with the slot should have gotten flagged as he clearly moved before the snap and as refbuz noted, he is not afforded protection. The CB saw it and pointed to it as well (not that that impacts whether or not you throw the flag, but it was discernible enough that it should be been flagged, IMO.) That said, while it is a foul, I'd like to see the rule changed to allow twitches like this scenario, where it was clearly in reaction to a defensive move, neutral zone or not, and there is no advantage gained from the movement. Had he had a defender directly over him, that would be a different story, IMO. But, rules are rules, and I have a foul here.
For the second, the wing did flag it - you can see him put his hand on it as soon as the both started their shift. I'd be curious as to whether he thought it was illegal from the start, and (correctly) waited until the snap to throw or if he saw the 2nd motion man still moving at the snap. I'm guessing he recognized the likelihood of the foul, and was being proactive in having the flag at the ready.