Link - Letting Generic Setup handle content types that may not exist
Saw this today and just saving the link for reference if I would run into this problem.
Fortunately there is an undocumented feature hidden in GS: You can declare your type declaration as deprecated. This way, GS does not try to initialize the object and does not try to create the type information object if it does not exist.
Read more: Link - How to handle unknown meta_type in GS — Starzel.de