Japanese embassys have been giving out Education visas to DTV applicants for some time now. It makes things really hard as the applicant then has a visa which is kind of not valid as its attached to a DTV gym that mostly are not licensed Education visa schools. So impossible to extend beyond the 3 months. Its really strange that they do this.
However the Japanese embassy in Tokyo contacted us today about 2 applicants and we were able to explain to them what's been going on. I think they might start actually issuing DTV now.
IF you apply soft power Muay Thai i think you will be fine. Hanoi tend to ask the question " how will you support your stay" it seems a tricky question but usually people just explain their financial circumstances truthfully with a bit of evidence, and Hanoi just accept it.
We sell courses in good faith and expect the student to turn up at some point. We allow for full flexibility and the classes can be taken at any time with no expiry date. But we are not asked to report or monitor attendance so if the student doesn't turn up we leave the classes on file and take the position that the course has been paid for, we are prepared to begin the course whenever the student is ready.