The problem here is because AMC is asking for a higher fee from the TV providers than it is worth. Walking Dead is hugely popular, but for organizations like cabel companies and Direct TV who are managing 100s of channels, AMC is not a keystone channel. They are trying to bully the bully and with the cabel operator blackout also happening soon. AMC is going to have to give in.
We have all been waiting to watch the Walking Dead and so AMC obviously knew that a lot of people were waiting to watch it. Which means they should have prepared for any blackouts that could occur with their partner DirecTV whom is just a broadcaster. Hence why I think AMC should take the blame!
If their is a black out to this one specific show then I believe that it would be the fault of the network. They have the ability to work with the shows producers and cast to ensure that it is produced and aired in a timely manner, any deviation from that would be the networks fault not the cable providers.
I think that if there is a Walking Dead Blackout, I would place the blame on both AMC and DirecTV for not being able to come to terms. AMC has been a part of a blackout before with another satellite provider so there has to be something they are doing in the negotiations that is playing a role. On the other hand, DirecTV is a large company with the means to pay AMC and could be trying to keep their pockets as fat as possible. No matter who is to blame, if it happens the customer loses.
I would blame DirecTV. They know the end product (Walking Dead) is hugely popular and commands many millions of weekly viewers. It is only fair and natural economics that this products high 'demand' would attract higher prices, whether DirecTV are willing to pay it or not. If they are not, expect to see subscribers going elsewhere if at all possible.