What neither of those polls show is the swing. On one poll there's a 4% increase for Labour, on another it's a 7% increase. Further data from yougov showed that only about 12% of people were really bothered about the story and most of them will be voters who are already tories.
This story is basically right wing people, whipping themselves into a frenzy, presenting incorrect information (that most of the public can see) and getting extremely (and increasingly angry) as nobody takes any notice of them. I kind of know this pattern, as this is what the far left are famed for. Positioning a narrative in such a way that it appears black and white, not really considering alternative assessments/interpretations of the event (and abusing people who try to provide this) and not taking any notice of what people outside their bubble say or think.
They have attacked Corbyn too much, and the public have grown immune to it. I always felt that it would have an immediate impact (which it did) but it would wear off. In the election the more personally they tried to attack Corbyn the worse the tories polls rating sunk and the more Labour's increased. There's only so much you can lie about someone until people think it's bullying (I do think there's a bit of that with Trump and the media, and possibly even May & the media).
That's the best case scenario for the Tories. That people agree with them but are basically sick of their conduct. The worst case scenario is that people like Jeremy Corbyn a lot, and that what they are chatting is extremely unpopular. For me it's the Lynton Crosby impact on the party. He is good at coming in at the last minute, spreading some dirt on opponents and getting a quick boost. It's not a long term strategy though which has been shown up.
From a left perspective, I hope they continue to attack Corbyn. It won't stick with the public. People see he is a decent principled bloke. Even if he's made mistakes he does so with the right intentions. People understand that.