I can find no sign that these fonts were ever supplied by Adobe. [Note: many Japanese fonts may include Adobe-Japan6 in the font description, but confusingly that does not mean Adobe is connected to them]. What makes you feel they should be in the Adobe font repository?
Because I simply choose these fonts from within Illustrator. I guess they were system fonts. Adobe's font repository leaves much to ask for when it comes to Japanese fonts so I'll probably have to source them elsewhere.