TellTale are just working within the (rather draconian) restrictions of Wii's online social structure. This situation seems to imply there is a tight restriction on the number of friends you can have per console and also that they can't remove you from their list right after sending the gift... but rather have too wait for you to accept it for some reason...
I got an email from them yesterday telling me to add a different system number instead of the one in the survey - this was my first email from them since filling it out. I immediately did as they asked and within a few short hours had already received and downloaded both episodes.
I also sent them funny thank you notes written in pirate-speak 

