No, even nobodies can be swallowed if they continually use the darkness. It's the very reason why they wear the cloaks.
...They also protect themselves with these cloaks... so as not to be swallowed by the darkness. Do you understand me? Not even the Organization can control the darkness.
I mentioned that the cloaks protects them against the darkness before. Since they don't belong to either light or darkness, they are shunned by both, which is why they wear those cloaks.
I think they're gonna use gummi ships cause in the first KH Cid used to own a gummi shop that he re-opened in the first KH so he must have owned it around the time of BBS.
I honestly doubt that. If BBS takes place 10 years before the first KH, and the first Gummi Ship appeared during the time of the heartless (courtesy of Mickey), then I doubt he could've known about the meteor material in BBS.
Ansem Report 9 said:Simply astonishing! Today I had a guest from another world. He is a king, and his vessel is built of the material that composed the meteors. He called the pieces "gummi blocks." It seemed that my opening the door has opened a path to interworld travel.
EDIT: AsYrsGoBy beat me to it.