if you’ve been approved for a DTV no you can’t what don’t you understand about passports being linked you can’t fool them you are not qualified to enter on anything other than the visa you have been approved for you can leave and enter a thousand times in 5 years if you like are you trying to save a month or too ??you can leave and use you other passport to do what you want but your not going to use it to enter Thailand other than activating your DTV