I find this whole buisness of Dina D’Malchusa quite interesting.
First off if their is a mitzva to drink on Purim it would apply to all those who are male and over the age of thirteen, period. In a case where the law of the land say expressly that oone may not fulfill a chiyuv it is questionable to say the least if one is obligated to fulfill Dina D”Malchusa.
As for the question of “are you so makpid regarding other chiyuvim” while the point is absurd in it’s own right I would just wish to ask. Are you makpid never to Jaywalk?