>>5717657because they run out of budget, switch to another form of adding extras (TB went from diorama pieces, stands, vehicles, other little figures, and BAFs), or the figure it was supposed to come with got canceled and suddenly it doesn't make sense to include the extra bit with anyone else.
Lots of reasons why something goes unreleased.
Lots of great figures like this will never be released. Sometimes, like Thorg, a character will be made over and over and never get released.
I really wish more comic figures were made.