i don't blame ts or his friend for being ignorant about the married status.
there are many people (especially chinese) who misunderstood this matter too.
for them, as long as they have not held their wedding dinner, they don't call themselves as married (although they already signed the marriage registration certificate).
i used to have colleagues who already registered their marriage but have not held their wedding dinner.
thus, they always introduce each other to people around as bf/gf.
after 5 years, they held their wedding dinner and then only start to introduce to people as husband/wife.
funny...