I called them today and wanted to know what can be done now and if there is any information. This is what i found out:

1) They confirmed, that they are under official supervision (i asked for the current management, so this tells me the same management is still in place, but they are being supervised)
2) They told me there's nothing anyone can do right now. (I explicitly asked if getting a lawyer is now necessary).
3) They told me there will be a new announcement today on the website (which is online by now, but tells nothing more anyway).

By checking the website i noted, that the callcenter in english language was removed: Its number is(was?): +81 3 4588 3922 (10am-5pm Tokio time).
If anyone else calls, please share your information here.