So I've just emailed the embassy in the Netherlands asking them if language school is also accepted. They replied with an pdf regarding all the visa's they have. The DTV one did not say language course unforteneley. So for now i would not take the risk and try to get an DTV based on this type of softpower.
im already at thai school now so if possible i would go to continue with learning the language at school. Ive sent an email to the embassy in the Netherlands if language school is valid.
You can also try different branches from Bangkok Bank, sometimes they let you open an account if you buy the insurance. Other option I've read is tell them you are buying a condo and you need an account