I think the later reports that William had visited there before are more likely to be correct
Due to reports that William had been at the previous year Community Christmas Party. The media have been shockingly bad with their reporting...backtracking and correcting themselves as they learn more.
I think that Williams Grandmother would have mentioned the families visit when talking to Mr Spedding - as this would be an important reason why she wanted the machine fixed - for their visit.
I can totally see this being an opportunistic kidnapping. It was a quiet street, nobody out on the road, lots of trees and bushes hiding views from neighbouring houses...even if the windows of grandmas had a clear view down the street...unless she (mum) had a reason to be staring out the window, which she wouldn't...someone easily could have driven up the road..saw William and on an impulse....had a very quick look around, stop grab William and bundle him into a car. He is only a little boy...I imagine he would be so shocked he wouldn't have even been able to scream... sadly most of the opportunistic abductions that I can remember...the little ones are not usually taken to be kept...rather these twisted individuals ..... take them somewhere quickly.. have their way with them and.....not a good outcome!!!