Will people who sign up at GetWisdom be put on a list to receive mind control manipulation by the Extraterrestrial Alliance, as happens with other channelers?

This is not the case. The reason is, you are not working for them, so they are not monitoring your activity and following along very closely as new members appear, to immediately engage with them and reel them in through subterfuge and manipulation. It always happens when people go to false channelers, they will be visited, they will be put under watch, and they will be manipulated to see how far they can be pushed to be disloyal and to be an agent of the Extraterrestrial Alliance working in opposition to humanity.