That is a bit about why they introduced a few more characters to the TV series, like the hacker girl, to make that black out of info a bit more plausible. In the books basically all the vamps, having lived for centuries, have accumulated vast amounts of wealth. The Master is basically using all his accumulated wealth, along with certain promises to high ranking government and media officials, to keep the info black out going during his assault. In the books there was more than just Palmer and the CDC chief, but they weren't really named characters either.
Also, in the books, NYC isn't the only city being assaulted like this. It just happens to be where the master is at. He actually has a few lieutenants assaulting pretty much all major world population centers about the same time doing what he is doing.
Another thing, whenever anything is posted about it on the internet, his human sympathizers are there to do whatever they can to get is dismissed by the masses. His shills make it seem like the posts or videos are fake movie trailers, or bad costumes, or whatever.
Finally, as his influence spreads, he has his vamps and some human sympathizers take out infrastructure related to media spread in the books globally. Communications go down and get spotty every where as the vamps spread.
Guessing the TV show doesn't have the ability to delve that deep so are using a few key characters to sort of convey about the same level of media black out. I don't think it's effective as the characters as basically doing computer "magic" to pull it off. Not quite as bad as swordfish, but I really hate computer magic.