I do not know how slaughtering these turkeys using halal and Kosher rules means BB is supporting terrorism.
What has been verified is that BB uses halal and Kosher rules for slaughter, they have not verified they yell islamic slogans.
“To be halal certified the animal must be facing Mecca, have its throat cut while still alive and then ritually sacrificed by a Muslim who recites a prayer dedicating the slaughter to Allah. Fees must be paid to one of the certifying organisations for this service. Islamic certifying organisations benefit financially from providing this service. They receive a constant stream of funds to support Islamic projects which contribute to the advancement of sharia (Islamic law) here and around the world.” source – Halal Choices
What does this have to do with supporting terrorism? First of all, they have to say a prayer while slaughtering the animals. Secondly, Butterball has to pay them to do this “service” and the money they pay them goes to terrorists. Oh, and they don’t have the right to sell meat sacrificed to idols (false gods) to unsuspecting consumers.