LOL @ people thinking Walt is forced to become the new cook. Do you guys really think after all the people who tried to force Walt to do something he doesn't want to do and end up dead these guys are the ones who succeed?
1) Walt has a deal with the guys and you most definitely don't Welsh on that group.
2) A man with a wife and two kids is a man who is easy to get leverage on.
If they want Walt to cook, Walt is cooking. At least temporarily until he can get the family safe, like maybe in New Hampshire.
The ricing part i have not figured out but honestly believe its gonna be used on Jesse but i could be wrong.
How about the ricin as a mercy killing? Let's say it plays out like:
AB kills Gomez, almost kills Hank, who is left paralyzed.
Walt has to cook for a little while, escapes to NH.
Gets family safely out of the way, comes back to settle score with AB and collect money.
Uses M-60 on the Aryans, uses the Ricin on Hank because Hank begs him to do it.